A fullscreen may refer to any of the following:
1. A full screen is any object or window that occupies the whole computer screen, covering up everything in the background. When a program or image is not fullscreen, it is referred to as a window or windowed. If a program and operating system support full-screen mode, click the maximize button to make a window fill the entire screen.
What is window fullscreen?
More commonly referred to as maximized, window fullscreen is any window or program that uses the entire screen but is still a window. With computer games, it's not uncommon for the game to have both a fullscreen (borderless fullscreen) and window fullscreen mode. When running a game in window fullscreen mode, you may notice a performance decrease, but you can switch between other programs quickly.
How to enter and exit fullscreen mode
In a browser on a Windows computer, you can enter fullscreen mode by pressing the F11 key. The key or method for entering fullscreen mode may vary in other programs. Computer games and other software that support fullscreen mode have an option in the display settings that allow you to specify if you want to run them as such.
Should I use "fullscreen," "full screen," or "full-screen" in my writing?
When describing a mode or setting, "fullscreen" or "full-screen" should be used as it's an adjective. As a noun, or when describing anything occupying the entire display or screen, "full screen" should be used.
2. Fullscreen format is a method used to modify the original copy of a movie to fit the aspect ratio of a TV or another display. During this formatting process, the movie's edges are trimmed, allowing it to fit on your screen. When a movie is displayed this way, a notice indicates that the movie is formatted to fit your screen. This practice is common as many movies are filmed in the 21:9 (ultrawide) aspect ratio, but most televisions display in 16:9 (widescreen).
3. Fullscreen, Inc., a media company founded in January 2011 by George Strompolos, helps YouTube creators with tools, optimization services, and consultation in finding an audience. On September 22, 2014, Fullscreen, Inc. became a subsidiary of Otter Media.
4. On Google Chromebook keyboards, there is a fullscreen key. Its identifying icon is a box with an arrow in the top-left and bottom-right corners, similar to the image shown. Pressing this key toggles the browser, usually Google Chrome, in and out of full-screen mode.
On non-Chromebook computers, the F11 function key is used to get into and out of fullscreen mode.