A screensaver (or screen saver) is a computer program that blanks the screen or fills it with moving images or patterns when the computer is not in use. The original purpose of screensavers was to prevent phosphor burn-in on CRT and plasma computer monitors (hence the name). Though modern monitors are not susceptible to this issue, screensavers are still used for other purposes. Screensavers are often set up to offer a basic layer of security, by requiring a password to re-access the device. Some screensavers use the otherwise unused computer resources to do useful work, such as processing for distributed computing projects.

As well as computers, modern television operating systems, media players and other digital entertainment systems include optional screensavers.

World Community Grid screensaver that uses idle system resources to help analyze proteins.


Screen protection

Before the advent of LCD screens, most computer screens were based on cathode ray tubes (CRTs). When the same image is displayed on a CRT screen for long periods, the properties of the exposed areas of phosphor coating on the inside of the screen gradually and permanently change, eventually leading to a darkened shadow or "ghost" image on the screen, called a screen burn-in. Cathode ray televisions, oscilloscopes and other devices that use CRTs are all susceptible to phosphor burn-in, as are plasma displays to some extent.

Screen-saver programs were designed to help avoid these effects by automatically changing the images on the screen during periods of user inactivity.

For CRTs used in public, such as ATMs and railway ticketing machines, the risk of burn-in is especially high because a stand-by display is shown whenever the machine is not in use. Older machines designed without burn-in problems taken into consideration often display evidence of screen damage, with images or text such as "Please insert your card" (in the case of ATMs) visible even when the display changes while the machine is in use. Blanking the screen is out of the question as the machine would appear to be out of service. In these applications, burn-in can be prevented by shifting the position of the display contents every few seconds, or by having a number of different images that are changed regularly.

Modern CRTs are much less susceptible to burn-in than older models due to improvements in phosphor coatings, and because modern computer images are generally lower contrast than the stark green- or white-on-black text and graphics of earlier machines. LCD computer monitors, including the display panels used in laptop computers, are not susceptible to burn-in because the image is not directly produced by phosphors (although they can suffer from a less extreme and usually non-permanent form of image persistence).

Modern usage

Gnome-screensaver has an option for password protection

While modern screens are not susceptible to the issues discussed above, screensavers are still used. Primarily these are for decorative/entertainment purposes, or for password protection. They usually feature moving images or patterns and sometimes sound effects.

As screensavers are generally expected to activate when users are away from their machines, many screensavers can be configured to ask users for a password before permitting the user to resume work. This is a basic security measure against another person accessing the machine while the user is absent.

Some screensavers activate a useful background task, such as a virus scan or a distributed computing application (such as the SETI@home project). This allows applications to use resources only when the computer would be otherwise idle.


Decades before the first computers using this technology were invented, Robert A. Heinlein gave an example of how they might be used in his novel Stranger In A Strange Land (1961):[1][2]

Opposite his chair was a stereovision tank disguised as an aquarium; he switched it on, guppies and tetras gave way to the face of the well-known Winchell Augustus Greaves.

The first screensaver was allegedly written for the original IBM PC by John Socha, best known for creating the Norton Commander; he also coined the term screen saver. The screensaver, named scrnsave, was published in the December 1983 issue of the Softalk magazine. It simply blanked the screen after three minutes of inactivity (an interval which could be changed only by recompiling the program).

By 1983 a Zenith Data Systems executive included "screen-saver" among the new Z-29 computer terminal's features, telling InfoWorld that it "blanks out the display after 15 minutes of nonactivity, preventing burned-in character displays".[3] The first screensaver that allowed users to change the activating time was released on Apple's Lisa, in 1983.

The Atari 400 and 800's screens would also go through random screensaver-like color changes if they were left inactive for about 8 minutes. Normal users had no control over this, though programs did. These computers, released in 1979, are technically earlier "screen savers." And prior to these computers, the 1977 Atari VCS/2600 gaming console included color cycling in games like Combat or Breakout, in order to prevent burn-in of game images to 1970s-era televisions. In addition, the first model of the TI-30 calculator from 1976 featured a screensaver, which consisted of a decimal point running across the display after 30 seconds of inactivity. This was chiefly used to save battery power, as the LED display was more power intensive than later LCD models. These are examples of screensavers in ROM or the firmware of a computer.

Today with the help of modern graphics technologies there is a wide variety of screensavers. Because of 3D computer graphics, which provide realistic environments, 3D screensavers are available.

Underlying architecture

Screensavers are usually designed and coded using a variety of programming languages as well as graphics interfaces. Typically the authors of screensavers use the C or C++ programming languages, along with Graphics Device Interface (GDI), DirectX, or OpenGL, to craft their final products. Several OS X screensavers are created and designed using Quartz Composer. The screensaver interfaces indirectly with the operating system to cause the physical display screen to be overlaid with one or more graphic "scenes". The screensaver typically terminates after receiving a message from the operating system that a key has been pressed or the mouse has been moved.

Microsoft Windows

If the system detects inactivity lasting longer than the time specified in the control panel, check if the active program is a simple program (and not another screensaver) by sending the "WM_SYSCOMMAND message" with the "SC_SCREENSAVE" argument. If the program calls in response the standard system function (DefWindowProc), the screensaver defined in the control panel screen runs.

A Windows screensaver is a regular Portable Executable (PE) with the .scr file extension. In addition, this program should support the following command line parameters:[4]

With no parameter – shows the Settings dialog box or do nothing.

ScreenSaver.scr /s

Runs the screensaver.

ScreenSaver.scr /p or /l <HWND>

Previews the screensaver as child of window. <HWND> (presented as unsigned decimal number) is an identifier (handle) of the window in which to appear preview.

ScreenSaver.scr /c

Shows the Settings dialog box, modal to the foreground window.

ScreenSaver.scr /a <HWND>

Changes password, modal to window <HWND>. Windows 95 screensavers must handle it.


Under MacOS, screensavers are regular MacOS application bundles with the .saver file extension[5].

Internally, the screensaver must define a class that is subclass of ScreenSaverView. The new class must be assigned as NSPrincipalClass in the xcode project, so that when the screensaver is launched by the system, this class gets instantiated.


As one of the first screensavers appeared in 8-bit Atari computers, forcing systemic color changes when the computer is idle lasting a few minutes (different times depending on the model), stored in the system ROM of the computer.


Monitors running screensavers consume the same amount of power as when running normally, which can be anywhere from a few watts for small LCD monitors to several hundred for large plasma displays. Most modern computers can be set to switch the monitor into a lower power mode, blanking the screen altogether. A power-saving mode for monitors is usually part of the power management options supported in most modern operating systems, though it must also be supported by the computer hardware and monitor itself.

Additionally, using a screensaver with a flat panel or LCD screen instead of powering down the screen can actually reduce the lifetime of the display, since the fluorescent backlight remains lit and ages faster than it would if the screen were turned off completely. As fluorescent tubes age they grow progressively dimmer, and they can be expensive or difficult to replace. A typical LCD screen loses about 50% of its brightness during a normal product lifetime, if left on continuously. (In most cases, the tube is an integral part of the LCD and the entire assembly needs to be replaced.)

Thus the term "screen saver" is now something of a misnomer – the best way to save the screen (and also save electricity consumed by screen) would simply be to have the computer turn off the monitor.


Xscreensaver xmatrix
XScreenSaver displaying a Matrix-style screensaver

After Dark was an early screensaver for the Macintosh platform, and later PC/Windows, which prominently featured whimsical designs such as flying toasters. Perhaps in response to the workplace environment in which they are often viewed, many screensavers continue this legacy of whimsy by populating the idle monitor with animals or fish, games, and visual expressions of mathematics equations (through the use of fractals, Fourier transforms or other means) as in the Electric Sheep screensaver.

At least one screensaver, Johnny Castaway told a humorous animated story over many months.[6] The ability of screensavers to divert and entertain is used for promotion, especially to build buzz for "event-based" products such as feature films.

The screensaver is also a creative outlet for computer programmers. The Unix-based screensaver XScreenSaver collects the display effects of other Unix screensavers, which are termed "display hacks" in the jargon file tradition of US computer science academics. It also collects forms of computer graphics effects called demo effects, originally included in demos created by the demo scene.

Microsoft Windows

On older versions of Microsoft Windows the native screensaver format had the potential to install a virus when run (as a screen saver was just an ordinary application with a different extension). When any file with the file suffix ".scr" was opened, for example from an e-mail attachment, Windows would execute the .scr (screensaver) file automatically: this had the potential to allow a virus or malware to install itself. Modern versions of Windows can read tags left by applications such as Internet Explorer and verify the publisher of the file, presenting a confirmation to the user.

On August 5, 2006, the BBC reported that "free screensavers" and "screensavers" respectively were the first and third most likely search terms to return links to malware, the second being BearShare.[7]

See also


  1. ^ Screensaver (Inventor of) by Robert Heinlein from Stranger in a Strange Land Archived March 18, 2015, at the Wayback Machine
  2. ^ Heinlein, Robert (1987). Stranger in a Strange Land. New York, NY: Penguin. p. 448. ISBN 9780441790340.
  3. ^ Chin, Kathy (1983-04-11). "Z-29, a new computer terminal from Zenith Data Systems". InfoWorld. InfoWorld Media Group, Inc. p. 13. Retrieved 2017-08-13.
  4. ^ "INFO: Screen Saver Command Line Arguments". Microsoft.
  5. ^ "ScreenSaverView - ScreenSaver | Apple Developer Documentation". Retrieved 2018-09-25.
  6. ^ Emrich, Alan; Wilson, Johnny L. (January 1993). "The Misadventures of Johnny Castaway". Computer Gaming World. p. 16. Retrieved 5 July 2014.
  7. ^ "Warning on search engine safety". BBC News. 2006-05-12. Retrieved 2010-06-07.

External links

After Dark (software)

After Dark is a series of computer screensaver software introduced by Berkeley Systems in 1989 for the Apple Macintosh, and in 1991 for Microsoft Windows.Following the original, additional editions included More After Dark, Before Dark, and editions themed around licensed properties such as Star Trek, The Simpsons, Looney Tunes, and Disney characters.On top of the included animated screensavers, the program allowed for the development and use of third-party modules, many hundreds of which were created by the height of After Dark's popularity.


Cozi is a website and mobile app intended to help families stay organized. Its features include allowing multiple family members to manage schedules with one account, as well as organize and update shopping and to-do lists.

The website was founded by Robbie Cape and Jan Miksovsky after the two of them left Microsoft. The company's first product, Cozi Central, was released on September 25, 2006, and included a family calendar, shopping lists, family messaging and a photo collage screensaver. The company is based in Seattle, Washington.

Cozi has both a freemium version, and a paid version called Cozi Gold. Cozi Gold's additional features include Cozi Contacts, a birthday tracker, more reminders, mobile month view, and change notifications.

Cozi was acquired by Time Inc. in 2014. After the Meredith Corporation acquired Time in 2018, Cozi was moved into the Parents Network division.

On June 5, 2011, Cozi set a Guinness World Record for the longest line of ducks in a row. The line stretched for one mile and was made up of 17,782 rubber ducks.

Crush (Pendulum song)

"Crush" is the fourth single from Australian drum and bass band Pendulum released from their third studio album, Immersion. Its release was set to coincide with the iTunes Immersion LP. The official video for the song was released on 7 January 2011 by BBC Radio 1 on their website. It was directed by Tim Qualtrough, who previously directed the official video for the single "Propane Nightmares". A "Crush" screensaver was released to promote the single.

Disney Junior (Dutch TV channel)

Disney Junior (formerly Playhouse Disney) is a Dutch pay television station for young children, owned by The Walt Disney Company. It only broadcasts at daytime between 6 AM and 6:55 PM. At night a screensaver is displayed. It is available in the Netherlands on Ziggo, Caiway, Caiway Albrandswaard and Caiway Cogas/Caiway Twente. In Flanders it is available on Telenet and Belgacom. Viewers in Wallonia, Brussels and Luxembourg receive the French version.

Electric Sheep

Electric Sheep is a distributed computing project for animating and evolving fractal flames, which are in turn distributed to the networked computers, which display them as a screensaver.

Frog (album)

Frog is an album by the Japanese noise musician Merzbow. It was inspired by frogs and utilizes their sounds. Masami Akita exhibited the audio and images at Yokohama Triennale 2001 in an installation called "Moss Garden" (苔庭, kokeniwa). It was reissued on CD in 2002, retitled Frog+, with a bonus disc of additional material and a screensaver.

Merzbow continued the frog theme on A Taste Of..., Puroland and Houjoue.

The album was used as source material for the remix album Frog Remixed and Revisited.

Funky Days!

Funky Days! (ファンキーデイズ!) is the fourth domestic single by Japanese hip-hop group Lead, released on July 30, 2003. It was their first to be released after their debut studio album Life On Da Beat, bringing in their new era of Brand New Era (2004). The single charted well on the Oricon charts at #10 and remained on the charts for five weeks.

Bonuses with the single included one of five possible trading cards, a URL in which fans could download a specialized wallpaper or screensaver, and a Lead 2003 Summer Campaign postcard.

GNOME Screensaver

Up until GNOME 3.5, GNOME Screensaver was the GNOME project's official screen blanking and locking framework. With the release of GNOME 3.5.5, screen locking functionality became a function of GDM and GNOME Shell by default.

Get Wild Life

Get Wild Life (stylized as GET WILD LIFE) is the fifth single by Japanese hip hop group Lead released on December 3, 2003. The single peaked in the top ten on the Oricon charts, ranking at #9 for the week, and remained on the charts for seven weeks.

The single came with several bonus items, including a Lead 2003 Winter Campaign postcard, one of five possible trading cards and a specialized URL to download a themed wallpaper and screensaver.

Google Pack

Google Pack was a collection of software tools offered by Google to download in a single archive. It was announced at the 2006 Consumer Electronics Show, on January 6. Google Pack was only available for Windows XP, Windows Vista, and Windows 7.

In September 2011, Google announced it would discontinue a number of its products, including Google Pack. Google Pack is no longer available for download.

Johnny Castaway

Johnny Castaway is a screensaver released in 1992 by Sierra On-Line/Dynamix, and marketed under the Screen Antics brand as "the world's first story-telling screen saver".

The screensaver depicts a man, Johnny Castaway, stranded on a very small island with a single palm tree. It follows a story which is slowly revealed through time. It takes many days to catch on to the story. While Johnny fishes, builds sand castles, and jogs on a regular basis, other events are seen less frequently, such as a mermaid or Lilliputian pirates coming to the island, or a seagull swooping down to steal his shorts while he is bathing. Much like the castaways of Gilligan's Island, Johnny repeatedly comes close to being rescued, but ultimately remains on the island as a result of various unfortunate accidents."Johnny Castaway" includes Easter eggs for a number of United States holidays such as Halloween, Christmas and Independence Day. During these holidays, the scenes are played out as usual except for some detail representing that holiday or event. During the last week of the year, for example, the palm tree will sport a "Happy New Year" banner, and on Halloween a jack-o'-lantern can be seen in the sand. The screensaver can be manipulated into showing these features by adjusting the computer clock to correspond with the date of the event.

The Johnny Castaway screensaver was distributed on a 3½-inch floppy disk and required a computer with a 386SX processor and Windows 3.1 as its operating system. Today, it is widely available on the internet, but as it relies on outdated 16-bit software components, it will only work on 32-bit versions of the Microsoft Windows operating system, which still support 16-bit applications, although workarounds exist for getting the screensaver to run on Windows 64-bit, Mac OS X and Linux.Character design was done by Shawn Bird while he was at Dynamix. The program had been developed at Jeff Tunnell Productions, the eponymous company of the original founder of Dynamix. According to Ken Williams, the screensaver was one of several products by Dynamix that were not costly to create and yet very profitable, like The Incredible Machine and Hoyle Card Games, also published by Sierra.

Kaspersky Lab

Kaspersky Lab (; Russian: Лаборатория Касперского, Laboratoriya Kasperskogo) is a multinational cybersecurity and anti-virus provider headquartered in Moscow, Russia and operated by a holding company in the United Kingdom. It was founded in 1997 by Eugene Kaspersky, Natalya Kaspersky, and Alexey De-Monderik; Eugene Kaspersky is currently the CEO. Kaspersky Lab develops and sells antivirus, internet security, password management, endpoint security, and other cybersecurity products and services.Kaspersky expanded abroad from 2005–2010 and grew to $698 million in annual revenues by 2017, up 8% from 2016, though annual revenues were down 8% in North America due to U.S. government security concerns. As of 2016, the software has about 400 million users and has the largest market-share of cybersecurity software vendors in Europe. Kaspersky Lab ranks fourth in the global ranking of antivirus vendors by revenue. It was the first Russian company to be included into the rating of the world's leading software companies, called the Software Top 100 (79th on the list, as of 6/29/2012). Kaspersky Lab is ranked 4th in Endpoint Security segment according to IDC data for 2010. According to Gartner, Kaspersky Lab is currently the third largest vendor of consumer IT security software worldwide and the fifth largest vendor of Enterprise Endpoint Protection. Kaspersky Lab has been named a "Leader" in the Gartner Magic Quadrant for Endpoint Protection Platforms.The Kaspersky Global Research and Analysis Team (GReAT) has discovered sophisticated espionage platforms linked to U.S. intelligence, such as Equation Group and the Stuxnet worm. Various covert government-sponsored cyber-espionage efforts were uncovered through their research. Kaspersky also publishes the annual Global IT Security Risks Survey. As of 2014, Kaspersky's research hubs analyze more than 350,000 malware samples per day.Kaspersky has faced controversy over allegations that it has engaged with the Russian Federal Security Service (FSB)—ties which the company has actively denied. The U.S. Department of Homeland Security banned Kaspersky products from all government departments on 13 September 2017. In October 2017, subsequent reports alleged that hackers working for the Russian government stole confidential data from the home computer of a National Security Agency contractor via Kaspersky antivirus software. Kaspersky denied the allegations, reporting that the software had detected Equation Group malware samples which it uploaded to its servers for analysis in its normal course of operation. The company has since announced commitments to increased accountability, such as soliciting independent reviews and verification of its software's source code, and announcing that it would migrate some of its core infrastructure for foreign customers from Russia to Switzerland.

Legacy of Kings

Legacy of Kings is the second album created by the Swedish metal band HammerFall. It was released on September 28, 1998, by Nuclear Blast Records.The enhanced CD release includes the music video for the track "Let the Hammer Fall", a photo gallery, lyrics for the songs, PC wallpapers, a screensaver, and a Winamp skin only on the Bonus Deluxe Edition. The cover art for this album was painted by Andreas Marschall.


A photofeed is a web feed that features image enclosures. They provide an easy, standard way to reference a list of images with title, date and description.

Photofeeds are RSS enclosures of image file formats, similar to podcasts (enclosures of audio file formats).

Screen Savers

Screen Savers or screensaver or variation, may refer to:

Screensaver, computer programs intended to preserve CRT monitors from "burn-in"

GNOME Screensaver, GNOME Project's screen blanking tool

Google Pack Screensaver, a terminal inactivity screen photo displayer included in the Google Pack

The Screen Savers, a technology-oriented television program that aired on TechTV and later G4

Tetris Splash

Tetris Splash is a puzzle video game, part of the Tetris games, was published by Microsoft Game Studios for the Xbox 360 via Xbox Live Arcade. It is the first game produced by Tetris Online, Inc.

The game gets its name from the aquarium background and water-themed music. Tetris Splash was released on the Xbox Live Arcade on October 3, 2007.


Webshots is a photo wallpaper and screensaver service owned and operated by Threefold Photos. It was also a photo sharing service from 1999 to 2012.


In computing, Winlogon is the component of Microsoft Windows operating systems that is responsible for handling the secure attention sequence, loading the user profile on logon, and optionally locking the computer when a screensaver is running (requiring another authentication step). The actual obtainment and verification of user credentials is left to other components.

Winlogon is a common target for several threats that could modify its function and memory usage. Increased memory usage for this process might indicate that it has been "hijacked".

In Windows Vista and later operating systems, Winlogon's roles and responsibilities have changed significantly.


XScreenSaver is a collection of 229 free screensavers for Unix, macOS, iOS and Android. It was created by Jamie Zawinski in 1992 and is still maintained by him.The free software and open-source Unix-like operating systems running the X Window System (such as Linux and FreeBSD) use XScreenSaver almost exclusively. On those systems, there are two parts to XScreenSaver: the collection of screen savers, and the framework for blanking and locking the screen.In recent years, some Linux distributions have been using the gnome-screensaver or kscreensaver screen-blanking frameworks by default instead of the framework included with XScreenSaver. They still depend on the XScreenSaver collection of screen savers, which is over 90% of the package, with the exception of gnome-screensaver version 3 and onward, which has dropped support for screensavers completely, supporting only simple screen blanking.. In December of 2018, Linux Mint released the 19.1 version of its Operational System, with Cinnamon 4.0.8, which doesn't support the XScreensaver hacks anymore. On Macintosh systems, XScreenSaver works with the usual Apple screen saver framework, and X11 is unneeded.In version 5.21 a time bomb has been introduced that displays large popups chastising the user for having an "outdated" version on login or interacting with XScreenSaver. The lock screen has similar wordage.XScreenSaver is released under the terms of the X11 License.

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