Screenshot

A screenshot is an image of what is visible on a visual output device such as a computer monitor or television. Usually, this is a digital image created by the operating system or software running on the device, but it can also be a photograph or a recording made by a device intercepting the video output of the display.

The first screenshots were created with the first interactive computers around 1960. Through the 1980s, computer operating systems did not universally have built-in functionality for capturing screenshots. Sometimes text-only screens could be dumped to a text file, but the result would only capture the content of the screen, not the appearance, nor were graphics screens preservable this way. Some systems had a BSAVE command that could be used to capture the area of memory where screen data was stored, but this required access to a BASIC prompt. Systems with composite video output could be connected to a VCR, and entire screencasts preserved this way.

Modern operating systems provide functions for creating screenshots. For example, on Windows devices, pressing PrtScr puts a screenshot of the entire desktop in the clipboard, where it is accessible to other software. In OS X, the command ⌘ Cmd+⇧ Shift+3 serves the same purpose. There are also a number of applications dedicated to taking screenshots, either provided with the operating system or available separately, that provide more control over which portion of the screen to capture.

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