Opera (web browser)

Opera is a web browser for Microsoft Windows, Android, iOS, macOS, and Linux operating systems[8][9], developed by Chinese-owned company Opera Software. Opera Software is a Norwegian software company[10] publicly listed on the NASDAQ stock exchange,[11] with the majority of ownership and control belonging to Chinese businessman Zhou Yahui, founder of Beijing Kunlun Tech[12] which specialises in mobile games and Chinese cybersecurity company Qihoo 360. Opera is a Chromium-based browser using the Blink layout engine. It differentiates itself because of a distinct user interface and other features.

Opera was conceived at Telenor as a research project in 1994 and was bought by Opera Software in 1995. It was a commercial software for the first ten years and had its own proprietary Presto layout engine. The Presto versions of Opera received many awards, but Presto development ended after the big transition to Chromium in 2013.

There are also three mobile versions called Opera Mobile, Opera Touch[13] and Opera Mini.

Opera 2015 icon
Opera 60 displaying the Wikipedia main page on Windows 10
Opera 60 displaying the Wikipedia main page on Windows 10
Developer(s)Opera Software
Initial release10 April 1995[1]
Stable release(s) [±]
60.0.3255.95 (May 16, 2019[2][3])
Preview release(s) [±]
beta60.0.3255.15 / March 27, 2019[4]
developer62.0.3323.0 / May 20, 2019[5]
Written inC++[6]
Operating systemWindows 7 or later,[7] macOS, Linux, Android, (formerly FreeBSD)
EnginesBlink (formerly Presto), V8
Available in42 languages
TypeWeb browser


Opera began in 1994 as a research project at Telenor, the largest Norwegian telecommunications company. In 1995, it branched out into a separate company named Opera Software.[14] Opera was first publicly released in 1996 with version 2.10,[15] which only ran on Microsoft Windows.[16] In an attempt to capitalize on the emerging market for Internet-connected handheld devices, a project to port Opera to mobile device platforms was started in 1998.[16] Opera 4.0, released in 2000,[15] included a new cross-platform core that facilitated the creation of editions of Opera for multiple operating systems and platforms.[17]

Up to this point, Opera was trialware and had to be purchased after the trial period ended. Version 5.0 (released in 2000) saw the end of this requirement. Instead, Opera became ad-sponsored, displaying advertisements to users who had not paid for it.[18] Later versions of Opera gave the user the choice of seeing banner ads or targeted text advertisements from Google. With version 8.5 (released in 2005) the advertisements were completely removed and the primary financial support for the browser came through revenue from Google (which is by contract Opera's default search engine).[19]

Among the new features introduced in version 9.1 (released in 2006) was fraud protection using technology from GeoTrust, a digital certificate provider, and PhishTank, an organization that tracks known phishing web sites.[20] This feature was further improved and expanded in version 9.5, when GeoTrust was replaced with Netcraft, and malware protection from Haute Secure was added.[21]

In 2006, Opera Software ASA was released as well as Internet Channel and Nintendo DS Browser for Nintendo's DS and Wii gaming systems.[22][23][24][25]

A new JavaScript engine called Carakan, after the Javanese alphabet, was introduced with version 10.50.[26] According to Opera Software, Carakan made Opera 10.50 more than seven times faster in SunSpider than Opera 10.10.[27][28][29] On the 16th of December 2010, Opera 11 was released, featuring extensions,[30] tab stacking (where dragging one tab over another allows you to create a group of tabs), visual mouse gestures and changes to the address bar.[31] Opera 12 was released on 14 June 2012.[32]

On the 12th of February 2013, Opera Software announced that it would drop its own Presto layout engine in favour of WebKit as implemented by Google's Chrome browser, using code from the Chromium project. Opera Software planned as well to contribute code to WebKit.[33] On the 3rd of April 2013, Google announced that it would fork components from WebKit to form a new layout engine known as Blink; the same day, Opera Software confirmed that it would follow Google in implementing the Blink layout engine.[34]

On the 28th of May 2013, a beta release of Opera 15 was made available,[35] the first version is based on the Chromium project.[36][37] Many distinctive Opera features of the previous versions were dropped, and Opera Mail was separated into a standalone application derived from Opera 12.[38]

Ownership structure of the Opera, after acquisition by the Chinese consortium, before the company get listed onto NASDAQ[39][40]

  ChinaZhou Yahui: Keeneyes Future Holdings (19.5%)
  ChinaZhou Yahui: Beijing Kunlun Tech (48%)
  ChinaQihoo 360: Qifei International Development Co. Limited (27.5%)
  ChinaGolden Brick Capital Private Equity Fund (5%)

In November 2016, the original Norwegian owner of Opera sold his stake in the business to a Chinese consortium under the name Golden Brick Capital Private Equity Fund I Limited Partnership for $600 million.[41][42][43] An earlier deal was not approved by regulators.[44]

In January 2017, the source code of Opera 12.15 (one of the last few versions that was still based on the Presto layout engine) was leaked.[45]

To demonstrate how radically different a browser could look, Opera Neon, dubbed a "concept browser", was released in January 2017. PC World compared it to demo models that automakers and hardware vendors release to show their visions of the future. Instead of a Speed Dial, it displays the frequently accessed websites in resemblance to a desktop with computer icons scattered all over it in an artistic formation.[46][47]


Opera has originated features later adopted by other web browsers, including Speed Dial, pop-up blocking, re-opening recently closed pages, private browsing, and tabbed browsing.[48][49] Opera includes a bookmarks bar and a download manager. Opera also has "Speed Dial", which allows the user to add an unlimited number of pages shown in thumbnail form in a page displayed when a new tab is opened. Speed Dial allows the user to more easily navigate to the selected web pages.[48][49][50]

Usability and accessibility

It is possible to control some aspects of the browser using the keyboard shortcuts.[51] Page zooming allows text, images and other content such as Adobe Flash Player, Java platform and Scalable Vector Graphics to be increased or decreased in size to help those with impaired vision.[52]

Opera Software claims that when the Opera Turbo mode is enabled, the compression servers compress requested web pages (except HTTPS pages) by up to 50%, depending upon the content, before sending them to the users.[53] This process reduces the amount of data transferred and is particularly useful for crowded or slow network connections, making web pages load faster or when there are costs dependent on the total amount of data usage.[53] This technique is also used in Opera Mini for mobile devices[54] and smartwatches.[55]

Privacy and security

One security feature is the option to delete private data, such as HTTP cookies, browsing history, items in cache and passwords with the click of a button.[56] This lets users erase personal data after browsing from a shared computer.

When visiting a site, Opera displays a security badge in the address bar which shows details about the website, including security certificates.[57] Opera’s fraud and malware Protection warns you about suspicious web pages and is enabled by default. It checks the requested page against several databases of known phishing and malware websites, called blacklists.[58]

In January 2007, Asa Dotzler of the competing Mozilla Corporation accused Opera Software of downplaying information about security vulnerabilities in Opera, (which were fixed in December 2006). Dotzler claimed that users were not clearly informed of security vulnerabilities that were present in the previous version of Opera and thus they would not realize that they needed to upgrade to the latest version or else risk being exploited by hackers.[59] Opera Software responded to these accusations on the next day.[60]

In 2016, a free virtual private network (VPN) service was implemented in the browser.[61] Opera said that this would allow encrypted access to websites otherwise blocked, and provide security on public WiFi networks.[62] Either VPN or Turbo can be enabled, but not both.[63]

In July 2018, Opera was listed on the NASDAQ stock exchange [64] in New York City at an initial offering of $12 per share.

Crypto Wallet Support

In 2018, a built-in cryptocurrency wallet to the Opera Web Browser was released.[65]. Announcing that they would be the first browser with a built-in Crypto Wallet[66]. On December 13, 2018 they released a video showing many decentralized applications like Cryptokitties running on the Android version of the Opera Web Browser[67].

Standards support

Opera was one of the first browsers to support Cascading Style Sheets (CSS).[68]

Development stages

Opera Software uses a release cycle consisting of three "streams" (which correspond to phases of development) that can be downloaded and installed independently of each other: "developer", "beta" and "stable". New features are first introduced in the developer build, then, depending on user feedback, may progress to the beta version and eventually be released.[69]

The developer stream allows early testing of new features, mainly targeting developers, extension creators, and early adopters. Opera developer is not intended for everyday browsing as it is unstable and is prone to failure or crashing, but it enables advanced users to try out new features that are still under development, without affecting their normal installation of the browser. New versions of the browser are released frequently, generally a few times a week.[70]

The beta stream, formerly known as "Opera Next", is a feature complete package, allowing stability and quality to mature before the final release. A new version is released every couple of weeks.[71]

Both streams can be installed alongside the official release without interference. Each has a different icon to help the user distinguish between the variants.

Market adoption

Desktop/laptop/tablet browser statistics
Google Chrome
Mozilla Firefox
Internet Explorer
Microsoft Edge
Desktop and tablet web browser market share according to StatCounter for March 2019.[72]

In 2005, Adobe Systems opted to integrate Opera's rendering engine, Presto, into its Adobe Creative Suite applications. Opera technology was employed in Adobe GoLive, Adobe Photoshop, Adobe Dreamweaver, and other components of the Adobe Creative Suite.[73][74] Opera's layout engine is also found in Virtual Mechanics SiteSpinner Pro.[75] The Internet Channel is a version of the Opera 9 web browser for use on the Nintendo Wii created by Opera Software and Nintendo.[76] Opera Software is also implemented in the Nintendo DS Browser for Nintendo's handheld systems.


Versions with the Presto layout engine have been positively reviewed,[77][78][79] although they have been criticized for website compatibility issues.[80][81] Because of this issue, Opera 8.01 and higher had included workarounds to help certain popular but problematic web sites display properly.[82][83]

Versions with the Blink layout engine have been criticized by some users for missing features such as UI customization, and for abandoning Opera Software's own Presto layout engine.[84][85][86][87] Despite that, versions with the Blink layout engine have been praised for being fast and stable, for handling the latest web standards and for having a better website compatibility and a modern-style user interface.[88][89][90]


Over the years, Opera for personal computers has received several awards. These awards include:[91]

  • About.com Best Major Desktop Browser - 2012[92]
  • About.com Best Major Desktop Browser - 2010[93]
  • Webware 100 winner, 2009[94]
  • Webware 100 winner, 2008[95]
  • PC World World Class Award, 2004 and 2005
  • Web Host Magazine & Buyer's Guide Editors' Choice
  • PC Magazine Testsieger (Test Winner), 2006
  • PC Plus Performance Award
  • PC World Best Data Product, 2003
  • PC World Best i Test, 2003
  • Web Attack Editor's Pick, 2003
  • ZDNet Editor's Pick, 2000
  • Tech Cruiser Award 4 Excellence, 1999

See also

Related web browsers:

  • Opera Mobile: a browser for tablets and telephones
  • Opera Mini: a browser for tablets and telephones
  • Otter Browser: An open-source web browser that aims to recreate some aspects of the classic Opera
  • Vivaldi: A freeware web browser by former Opera Software employees who were not satisfied by the development decisions of the company

Web browsers:

Essential features:


  1. ^ "Opera version history — Opera 1 series". Opera Software. 21 February 2012. Retrieved 21 February 2012.
  2. ^ Czajka, Joanna. "Opera introduces Reborn 3, the first desktop browser with Web 3, faster VPN and ad blocker". Opera Blogs. Opera Software. Retrieved 14 April 2019.
  3. ^ "Index of /pub/opera/desktop/". Retrieved 14 April 2019.
  4. ^ "Opera 59 codenamed Reborn 3 reaches beta stage". 28 February 2019. Retrieved 11 March 2019.
  5. ^ "Opera 62.0.3323.0 developer update". 20 May 2019. Retrieved 20 May 2019.
  6. ^ Lextrait, Vincent (July 2010). "The Programming Languages Beacon, v10.3". Archived from the original on 30 May 2012. Retrieved 11 June 2014.
  7. ^ "Opera system requirements". Opera Software. Retrieved 22 March 2018.
  8. ^ https://www.opera.com/download/requirements
  9. ^ https://www.opera.com/mobile
  10. ^ https://www.opera.com/about
  11. ^ https://www.nasdaq.com/symbol/opra
  12. ^ "Chinese consortium buys Opera browser for $600 mn". phys.org. Retrieved 23 April 2019.
  13. ^ https://www.opera.com/pl/mobile/touch
  14. ^ "About Opera". Opera Software. Archived from the original on 3 December 2007. Retrieved 5 September 2010.
  15. ^ a b "Affiliated Organization of Firefox and Mozilla" (PDF). Mozilla Japan. Mozilla Foundation. 2006. Retrieved 5 September 2010.
  16. ^ a b "Milestones". Opera Software. 2007. Archived from the original on 23 November 2007. Retrieved 13 January 2011.
  17. ^ Schenk, Mark (2010). "Opera browser version history". Retrieved 11 June 2014.
  18. ^ Lettice, John (6 December 2000). "Opera browser goes free with version 5.0 launch". The Register. Retrieved 11 June 2014.
  19. ^ Baker, Loren (20 September 2005). "Opera Goes Free with Help from Google". Search Engine Journal. Retrieved 11 June 2014.
  20. ^ Goldman, Daniel (18 December 2006). "Opera 9.1 is out with Fraud Protection". Opera Watch. Archived from the original on 5 January 2007. Retrieved 11 June 2014.
  21. ^ Kleinhout, Huib (6 June 2008). "Malware protection". Opera Desktop Team. Opera Software. Archived from the original on 8 June 2008. Retrieved 11 June 2014.
  22. ^ "Giving gamers two windows to the Web: The Opera Browser for Nintendo DS" (Press release). Opera Software. 15 February 2006. Retrieved 11 June 2014.
  23. ^ "Nintendo DS Browser available to North American market" (Press release). Opera Software. 8 June 2007. Retrieved 11 June 2014.
  24. ^ "A Web Revolution in the Living room: Opera partners with Nintendo to put browser on the Wii game console" (Press release). Opera Software. 10 May 2006. Retrieved 11 June 2014.
  25. ^ "Play with the Web: Opera browser now available for download on Wii" (Press release). Opera Software. 22 December 2006. Retrieved 11 June 2014.
  26. ^ "Opera 10.50 for Windows changelog (Final)". Opera Software. 2 March 2010. Retrieved 11 June 2014.
  27. ^ Mateu, Roberto (1 January 2010). "Opera 10.5 pre-alpha for Labs". Opera Labs. Opera Software. Archived from the original on 24 December 2009. Retrieved 11 June 2014.
  28. ^ De, Pallab (22 December 2009). "Opera 10.5 Pre-Alpha Is Here and It Is Fast!". Techie-buzz.com. Retrieved 11 June 2014.
  29. ^ Purdy, Kevin (22 December 2009). "Opera 10.5 Pre-Alpha is All About Speed (and Private Browsing)". Lifehacker. Gawker Media. Retrieved 11 June 2014.
  30. ^ Protalinski, Emil (21 October 2010). "Opera 11 alpha out: developers, start your extension engines". Ars Technica. Missing or empty |url= (help)
  31. ^ "Opera 11.00 for Windows changelog". Opera Software. Retrieved 11 June 2014.
  32. ^ "Opera 12.00 for Windows Changelog". Opera Software. 14 June 2012. Retrieved 11 June 2014.
  33. ^ "Hey Presto, Opera switches to WebKit". Ars Technica. Condé Nast. Retrieved 4 April 2013.
  34. ^ Opera Desktop Team - Opera Next 15 Released!. My.opera.com (28 May 2013). Retrieved on the 21st of July 2013.
  35. ^ Opera Developer News - A first peek at Opera 15 for Computers. My.opera.com (28 May 2013). Retrieved on 21 July 2013.
  36. ^ The Chromium-Powered Opera Is Finally Here. WebProNews (28 May 2013). Retrieved on 21 July 2013.
  37. ^ Standalone Opera Mail Client Coming to Linux. Omgubuntu.co.uk (28 May 2013). Retrieved on 21 July 2013.
  38. ^ "昆仑万维参股公司Opera Limited拟赴美上市". Reuters (in Chinese). 2 July 2018. Retrieved 2 July 2018.
  39. ^ "Shareholder Structure | Opera Limited". opera.gcs-web.com. Retrieved 4 September 2018.
  40. ^ "BRIEF-Opera Software says has closed $575 mln with China's Golden Brick". Reuters. 4 November 2016. Retrieved 20 May 2017.
  41. ^ Lunden, Ingrid. "Opera renegotiates its $1.2B sale down to $600M for its browsers, privacy apps, Chinese JV". TechCrunch. Retrieved 20 May 2017.
  42. ^ "NewsWeb". www.newsweb.no. Retrieved 7 January 2017.
  43. ^ "Opera browser sold to a Chinese consortium for $600 million". Engadget. Retrieved 19 May 2017.
  44. ^ Presto engine source code available on GitHub (2017)
  45. ^ Hachman, Mark (11 January 2017). "Meet Opera Neon, Opera's radical vision for the future of web browsers". PCWorld.
  46. ^ Muchmore, Michael (11 January 2017). "Opera Neon". PC Magazine.
  47. ^ a b "5 features Opera Browser did first". SlashGeek. Retrieved 5 October 2016.
  48. ^ a b Reimer, Jeremy (1 September 2009). "First look: Opera 10 faster with new features". Ars Technica. Condé Nast. Retrieved 11 June 2014.
  49. ^ "Opera version history". Opera. Retrieved 29 February 2016. Opera has a history of introducing new features long before they become mainstream, and often failing to receive credit for doing so. Opera was the first browser to [...]
  50. ^ "Help, Fast browsing". Opera Software. Retrieved 12 June 2014.
  51. ^ "Help, View webpages". Opera Software. Retrieved 12 June 2014.
  52. ^ a b "Opera's company FAQ". Opera Software. Retrieved 12 June 2014.
  53. ^ "Opera Turbo". Opera Software. Archived from the original on 30 June 2010. Retrieved 5 September 2010.
  54. ^ "Samsung Gear S now features a full web browser". CompareSmartwatches.com. Retrieved 8 October 2014.
  55. ^ "Help, Be safe and private". Opera Software. Retrieved 12 June 2014.
  56. ^ https://help.opera.com/en/latest/security-and-privacy/#securityBadges
  57. ^ https://help.opera.com/en/latest/security-and-privacy/#phishingAndMalware
  58. ^ Kerner, Sean Michael (9 January 2007). "Mozilla Takes Aim at Opera Security". Internetnews.com. Retrieved 11 June 2014.
  59. ^ Kerner, Sean Michael (10 January 2007). "Opera Has Words For Mozilla". Internetnews.com. Retrieved 11 June 2014.
  60. ^ "Free VPN". Opera.com. Retrieved 18 March 2017.
  61. ^ "Opera Free VPN - Unlimited WiFi Security & Content Unblocking - Free VPN for online security, unblocking content and encrypting your web traffic". Opera VPN. 2017. Retrieved 18 March 2017.
  62. ^ Opera Settings > VPN: "Enabling VPN will disable Opera Turbo"
  63. ^ https://www.cnet.com/news/opera-browser-raises-115-million-in-initial-public-offering/
  64. ^ https://invidio.us/watch/?v=aq5yJ0TqhbY
  65. ^ https://archive.is/EDjGJ
  66. ^ https://www.youtube.com/watch/?v=aq5yJ0TqhbY
  67. ^ Meyer, Eric (June 1999). "CSS: If not now, when?". meyerweb.com. Retrieved 11 June 2014.
  68. ^ "What is Opera, Opera next, and Opera developer?". Opera Desktop Team Blog. Retrieved 16 September 2014.
  69. ^ "Opera Developer official page". Opera Software. Retrieved 20 November 2013.
  70. ^ "Opera beta". Opera Software ASA. Retrieved 9 November 2014.
  71. ^ "Desktop & Tablet Browser Market Share Worldwide". StatCounter Global Stats. Retrieved 3 April 2019.
  72. ^ "Powered by Opera: Opera Integrated with Adobe Creative Suite 2" (Press release). Opera Software. 4 April 2005. Retrieved 11 June 2014.
  73. ^ Goldman, Daniel (3 May 2007). "Dreamweaver uses Opera's Small-Screen Rendering technology to preview webpages for mobile phones". Opera Watch. Archived from the original on 11 November 2007. Retrieved 11 June 2014.
  74. ^ "Design Web Pages for the Desktop and Mobile Devices" (Press release). Virtual Mechanics Inc. 17 November 2008. Archived from the original on 9 January 2009. Retrieved 11 June 2014.
  75. ^ "Archived copy". Archived from the original on 26 May 2014. Retrieved 8 July 2014.CS1 maint: Archived copy as title (link)
  76. ^ Stieben, Danny (24 May 2012). "5 Ideological Reasons Why You Should Try Opera". makeuseof.com. Retrieved 12 June 2014.
  77. ^ Mason, Wesley (16 March 2000). "Software Review: Opera browser for Windows v3.62". Geek.com. Retrieved 6 September 2010.
  78. ^ Berger, Sandy (3 November 2004). "Opera Web Browser". CompuKiss. Archived from the original on 12 November 2004. Retrieved 6 September 2010.
  79. ^ Altman, Tim (31 August 2007). "Focus Areas during Kestrel Development". Opera Desktop Team. Opera Software. Archived from the original on 4 September 2007. Retrieved 6 September 2010.
  80. ^ Dotzler, Asa (4 September 2007). "Firefox and more". Archived from the original on 20 October 2007. Retrieved 6 September 2010.
  81. ^ "Browser JavaScript Explained". Opera Software. Retrieved 11 June 2014.
  82. ^ "Changelog for Opera 8.01 for Windows". Opera Software. Retrieved 11 June 2014.
  83. ^ Harac, Ian (9 December 2013). "Opera 18 review: This browser's seen radical changes… perhaps too radical". PC World. IDG. Retrieved 12 June 2014.
  84. ^ Samson, Ted. "Blink-based Opera 15 strikes a sour note with users". InfoWorld. IDG. Retrieved 29 July 2013.
  85. ^ Mathews, Lee (2 July 2013). "Opera 15 launches, turns out to be a crippled Google Chrome". geek.com. Ziff Davis. Retrieved 12 June 2014.
  86. ^ Keizer, Gregg. "Opera 15 launches with WebKit backbone". Computer World. Retrieved 29 July 2013.
  87. ^ Le Bihan, Alan (26 May 2014). "A browser that's free, comprehensive and innovative". Softonic.com. Retrieved 12 June 2014.
  88. ^ Piccolomini, Pier Francesco (5 September 2013). "5 Alternatives to Internet Explorer". Softonic.com. Retrieved 12 June 2014.
  89. ^ Hughes, Matthew (6 August 2013). "Opera 15 Is A Faster, Simpler Chrome, And Here Are 3 Great Reasons To Try It". Makeuseof.com. Retrieved 12 June 2014.
  90. ^ "Awards". Opera Software. Archived from the original on 22 January 2011. Retrieved 11 June 2014.
  91. ^ "Web Browsers Poll Results". About.com. 2012. Retrieved 11 June 2014.
  92. ^ Orgera, Scott (2010). "The 2010 Reader's Choice Awards Winners: Web Browsers". About.com. Retrieved 11 June 2014.
  93. ^ "Webware 100 2009". Webware.com. 2009. Archived from the original on 18 July 2009. Retrieved 11 June 2014.
  94. ^ "Welcome to Webware 100 Awards 2008". 2008. Archived from the original on 12 May 2008. Retrieved 11 June 2014.

External links

Features of the Opera web browser

This article details features of the Opera web browser.


hCalendar (short for HTML iCalendar) is a microformat standard for displaying a semantic (X)HTML representation of iCalendar-format calendar information about an event, on web pages, using HTML classes and rel attributes.

It allows parsing tools (for example other websites, or browser add-ons like Firefox's Operator extension) to extract the details of the event, and display them using some other website, index or search them, or to load them into a calendar or diary program, for instance. Multiple instances can be displayed as timelines.

History of the Opera web browser

The history of the Opera web browser began in 1994 when it was started as a research project at Telenor, the largest Norwegian telecommunications company. In 1995, the project branched out into a separate company named Opera Software ASA, with the first publicly available version released in 1996. Opera has undergone extensive changes and improvements, and introduced notable features such as Speed Dial.

Until version 2.0, the Opera browser was called MultiTorg Opera (version 1.0) and had only a limited internal release—although it was demonstrated publicly at the Third International WWW Conference in April 1995. It was known for its multiple document interface (MDI) and 'hotlist' (sidebar), which made browsing several pages at once much easier, as well as being the first browser to completely focus on adhering to the W3C standards.In February 2013, Opera Software announced that their in-house rendering engine, Presto, would be phased out in favour of WebKit. Opera 15 saw the browser being fully rewritten, with this and subsequent releases being based on Blink and Chromium.

List of ECMAScript engines

An ECMAScript engine is a program that executes source code written in a version of the ECMAScript language standard, for example, JavaScript.

These are new generation ECMAScript engines for web browsers, all implementing just-in-time compilation (JIT) or variations of that idea. The performance benefits for just-in-time compilation make it much more suitable for web applications written in JavaScript.

Carakan: A JavaScript engine developed by Opera Software ASA, included in the 10.50 release of the Opera web browser, until switching to V8 with Opera 15 (released in 2013).

Chakra (JScript9): A JScript engine used in Internet Explorer. It was first previewed at MIX 10 as part of the Internet Explorer 9 Platform Preview.

Chakra: A JavaScript engine used in Microsoft Edge.

SpiderMonkey: A JavaScript engine in Mozilla Gecko applications, including Firefox. The engine currently includes the IonMonkey compiler and OdinMonkey optimization module, has previously included the TraceMonkey compiler (first javascript JIT) and JägerMonkey.

JavaScriptCore: A JavaScript interpreter and JIT originally derived from KJS. It is used in the WebKit project and applications such as Safari. Also known as Nitro, SquirrelFish and SquirrelFish Extreme.

Tamarin: An ActionScript and ECMAScript engine used in Adobe Flash.

V8: A JavaScript engine used in Google Chrome, Node.js, and V8.NET.

Nashorn: A JavaScript engine used in Oracle Java Development Kit (JDK) since version 8.

iv, ECMAScript Lexer / Parser / Interpreter / VM / method JIT written in C++

CL-JavaScript: Can compile JavaScript to machine language on Common Lisp implementations that compile to machine languageThe following engines use runtime interpreters, which do not compile into native machine code and generally run more slowly:

Continuum: A self-interpreter that supports older drafts of the ECMAScript 2015 specification. Uniquely, the engine is implemented in ECMAScript 3, which made it possible to run ES2015 in browsers as old as IE6.

Futhark: The ECMAScript engine of the Opera web browser versions 9.50 to 10.10.

InScript: An obsolete proprietary library used for iCab 2 and 3.

JScript: The engine that is used in Internet Explorer for versions up to IE9, and one component of the Trident layout engine.

KJS: The engine used in Konqueror, and one component of KHTML, a predecessor to JavaScriptCore.

Linear B: The ECMAScript engine of the Opera web browser versions 7.0 to 9.50, exclusive.

Narcissus: JavaScript implemented in JavaScript (a meta-circular evaluator), intended to run in another JavaScript engine, of theoretical and educational nature only.

JS-Interpreter A lightweight JavaScript interpreter implemented in JavaScript with step-by-step execution.

QtScript: Originally developed by Trolltech, now owned by The Qt Company. It provides QObject integration with JavaScriptCore.

Rhino: One of several JavaScript engines from Mozilla, using the Java platform.

YAJI: An ECMAScript engine based on the FESI implementation by Jean-Marc Lugrin in 1999, using the Java platform, currently being developed to support the latest standards (ECMAScript spec. 262, v5.1).

Duktape: A small footprint, easily embeddable Ecmascript E5/E5.1 engine.

The Kinoma Platform, an ECMAScript 6 runtime environment and framework. This is one of the first runtimes to correctly implement almost all of the ECMAScript 6 specification, currently unmaintained.

Moddable successor of Kinoma Platform, currently active project and aims to support more recent versions of ECMAScript.

Jsish: A JavaScript interpreter with builtin SQLite, JSON, WebSocket, and ZVFS support.

Websocket.js: An embeddable Javascript engine with HTTP/Websocket support.

Espruino: A very small footprint interpreter specifically for microcontrollers. Can run in less than 8 kB of RAM by executing from source (rather than bytecode).

MuJS: A lightweight ECMAScript interpreter library, designed for embedding in other software to extend them with scripting capabilities. Originally developed for MuPDF.

V7: Part of the Smart.js platform; claims to be the world's smallest JavaScript engine.

Tiny-JS: A minimal JavaScript interpreter written in C++.

JerryScript: A lightweight JavaScript engine by Samsung for microcontrollers with less than 64 KB RAM.

GNU Guile features an ECMAScript interpreter as of version 1.9

njs: A lightweight JavaScript interpreter optimized for web server scripting and fastest VM context creation; used in nginx.

List of Nintendo DS accessories

This is a list of Nintendo DS accessories.

My Opera

My Opera was the virtual community for Opera web browser users. It belonged to Opera Software ASA. In addition to being a support site for the Opera browser, My Opera worked like a social networking site. It offered services such as blogs, photo albums, the free email service My Opera Mail and more. My Opera was closed down on March 3, 2014.

Mylo (Sony)

My Life Online (mylo) is a device created and marketed by Sony for portable instant messaging and other Internet-based communications, browsing Internet web sites (using the Opera web browser) and playback and sharing of media files. The pocket-sized, tablet-shaped handheld device, which debuted in 2006, had a screen which slid up to reveal a QWERTY keyboard. The brand name 'mylo' stands for My Life Online. Using Wi-Fi instead of cellular networks, the mylo was targeted to the 18–24 age group.By using WiFi networks for Internet connectivity, mylo provided users with the possibility of reducing connectivity costs by avoiding the necessity of using GSM, CDMA or 3G cellular networks which would usually be used for devices of this size and functionality.

Odin (software)

In computing, Odin is a project to run Microsoft Windows programs on OS/2 or convert them to OS/2 native format. It also provides the Odin32 API to compile Win32 (Windows API) programs for OS/2.

The project's goals are:

Every Windows program should load and operate properly;

Create a complete OS/2 implementation of the Win32 API.Although this is far from complete, much of the Win32 API is not widely used, so partial implementation will give usable results. Odin32 is already used commercially for the OS/2 port of the Opera web browser.

Opera Dragonfly

Opera Dragonfly is a web development tool that was integrated into the Opera web browser from Opera versions 9.5 through 12.18, similar to Firebug and development tools built into Mozilla Firefox and Google Chrome.

It supports debugging JavaScript, viewing the DOM, monitoring network traffic, previewing resources, editing colors, etc. It also supports remote debugging, which allows using the features of Dragonfly to be used when debugging a mobile phone, TV, or another desktop computer.Opera Dragonfly must be downloaded on first usage, and functions offline thereafter. Opera Dragonfly automatically updates to the latest version available, when connected to the Internet.Opera Dragonfly is compatible with Presto 2.1 and later, specifically Opera Mobile 9.5 and above, Opera Desktop 9.5 and above, and Nintendo DS & Nintendo DSi Browser.

The Scope transport protocol (STP) is used for communication between the Opera browser and Opera Dragonfly.

Opera Mail

Opera Mail (formerly known as M2) is the email and news client developed by Opera Software. It was an integrated component within the Opera web browser from version 2 through 12. With the release of Opera 15 in 2013, Opera Mail became a separate product and is no longer bundled with Opera. Opera Mail version 1.0 is available for OS X and Windows. It features rich text support and inline spell checking, spam filtering (both automated and Bayesian), a contact manager, and supports POP3 and IMAP, newsgroups, and Atom and RSS feeds.

Opera Mail uses one database that keeps an index of all mail and sorts the messages automatically into several "views" or access points. Messages are automatically sorted by types, such as mailing lists, and mail with attachments. This approach to indexing allows for quicker access to messages. For instance, a message sent to a mailing list with a word document attached will appear in both the "Documents" attachment view and in the "Mailing lists" view. Opera Mail can also use Bayesian filtering to automatically sort messages into other views. All messages in the database are accessed by opening the "Received" view.

The integrated mail component included a simple IRC client, but this is no longer present in the standalone program. The IRC client supported multiple servers, file transfers, and interface customization through CSS.

Opera Mail can display text and HTML emails and uses the Presto layout engine to display HTML.

Opera Mail is at the end-of-life stage of its product lifecycle; this means neither technical support nor product and security updates will be provided. The product is no longer available for download.

Opera Mini

Opera Mini is a mobile web browser developed by the Opera Limited company. It was primarily designed for the Java ME platform, as a low-end sibling for Opera Mobile, but it is now developed exclusively for Android and iOS. It was previously developed for Windows 10 Mobile, Windows Phone 8.1, BlackBerry, Symbian, and Bada. Those versions are still maintained, despite not being developed.

Opera Mini was derived from the Opera web browser. Opera Mini requests web pages through Opera Software's compression proxy server. The compression server processes and compresses requested web pages before sending them to the mobile phone. The compression ratio is 90% and the transfer speed is increased by two to three times as a result. The pre-processing increases compatibility with web pages not designed for mobile phones. However, interactive sites which depend upon the device processing JavaScript do not work properly.

In July 2012, Opera Software reported that Opera Mini had 168.8 million users as of March 2012. In February 2013, Opera reported 300 million unique Opera Mini active users and 150 billion page views served during that month. This represented an increase of 25 million users from September 2012.

Opera Software

Opera Software AS is a Chinese-owned software company, primarily known for its desktop Opera web browser, and mobile web browser Opera Mini. It was demerged from its parent company Otello Corporation as part of the latter's divestiture of its web browser business. Opera browsers have more than 350 million users worldwide across multiple platforms.Opera is also involved in promoting Web standards through participation in the W3C. The company has its headquarters in Oslo, Norway and also has offices in Sweden, Poland, China, Japan, South Korea, Australia, Russia, Ukraine, Iceland, Singapore, Taiwan and the United States.The company changed ownership when Otello (at the time Opera Software ASA) sold its web browser and consumer businesses along with the Opera brand to a Chinese group of investors in 2016 with the deal completing in November of that year.On July 27, 2018, Opera Software went public on the NASDAQ stock exchange, raising $115 million in its initial public offering.

Otter Browser

Otter Browser is a cross-platform, free and open-source web browser that aims to recreate aspects of Opera 12.x using Qt framework while keeping seamless integration with users' desktop environments. Otter Browser is licensed under GPLv3. It works on Linux, macOS, and Windows platforms.The Qt WebEngine used by Otter is a wrapper around the Chromium browser core.

Palm Foleo

The Palm Foleo was a planned subnotebook computer that was announced by mobile device manufacturer Palm Inc. on May 30, 2007, and canceled three months later. It intended to serve as a companion for smartphones including Palm's own Treo line. The device ran on the Linux operating system and featured 256 MB of flash memory and an immediate boot-up feature.The Foleo featured wireless access via Bluetooth and Wi-Fi. Integrated software included an e-mail client which was to be capable of syncing with the Treo E-Mail client, the Opera web browser and the Documents To Go office suite. The client did not send and retrieve mail over the Wi-Fi connection, instead transmitting via synchronization with the companion smartphone.The device was slated to launch in the U.S. in the third quarter of 2007 for a price expected by Palm to be $499 after an introductory $100 rebate. Palm canceled Foleo development on September 4, 2007, with Palm CEO Ed Colligan announcing that the company would return its focus to its core product of smartphones and handheld computers. Soon after the device was canceled, a branch of subnotebooks called netbooks, similar to the Foleo in size and functionality, reached the market. Had it been released, the Foleo would have been the founding device in the category. At the time, Palm was performing poorly in face of heavy competition in the smartphone market. The company's sales did not recover, and it was purchased by information technology giant Hewlett-Packard in April 2010.

Presto (browser engine)

Presto was the browser engine of the Opera web browser from the release of Opera 7 on 28 January 2003 until the release of Opera 15 on 2 July 2013, at which time Opera switched to using the Blink engine that was originally created for Chromium. Presto was also used to power the Opera Mini and Opera Mobile browsers.

Presto is a dynamic engine. Web pages can be re-rendered completely or partially in response to DOM events. Its releases saw a number of bug fixes and optimizations to improve the speed of the ECMAScript (JavaScript) engine. It is proprietary and only available as a part of the Opera browsers.

Server-sent events

Server-sent events (SSE) is a server push technology enabling a browser to receive automatic updates from a server via HTTP connection. The Server-Sent Events EventSource API is standardized as part of HTML5 by the W3C.

Sidebar (computing)

The sidebar is a graphical control element that displays various forms of information to the right or left side of an application window or operating system desktop. Examples of the sidebar can be seen in the Opera web browser, OpenOffice.org, SoftMaker Presentations and File Explorer; in each case, the app exposes various functionalities via the sidebar.


WebKit is a browser engine used in Apple's Safari browser and other products.

WebKit is also the basis for the experimental browser included with the Amazon Kindle e-book reader, and for the default browser in Apple iOS, BlackBerry Browser in OS 6 and above, and Tizen mobile operating systems. WebKit's C++ application programming interface (API) provides a set of classes to display web content in windows, and implements browser features such as following links when clicked by the user, managing a back-forward list, and managing a history of pages recently visited.

WebKit's HTML and JavaScript code was originally a fork of the KHTML and KJS libraries from KDE, and has now been further developed by people from KDE, Apple, Google, Nokia, Bitstream, BlackBerry, Igalia, and others. macOS, Windows, Linux, and some other Unix-like operating systems are supported by the project. On April 3, 2013, Google announced that it had forked WebCore, a component of WebKit, to be used in future versions of Google Chrome and the Opera web browser, under the name Blink.WebKit is available under a BSD-form license with the exception of the WebCore and JavaScriptCore components, which are available under the GNU Lesser General Public License. As of March 7, 2013, WebKit is a trademark of Apple, registered with the U.S. Patent and Trademark Office.

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