Function keys appeared with the release of the IBM PC / XT personal computers in 1983 and were used to quickly access frequently used functions. Over the past thirty-odd years, their appointment has remained the same.
Main purpose
The actions performed by pressing each of the twelve function buttons may differ depending on the operating system or even the application, but there are universal assignments.
On the first PC / XT keyboard, where function keys appeared, there were only ten of them, and they were located on the left in two rows.
F1 is the help key. It works almost everywhere - from old text-based applications to modern applications, in Windows operating systems, in many GNU / Linux distributions. The only exception is Mac OS.
F2. Its common function is editing. In Windows Explorer, pressing F2 renames the file; in some file managers, it opens the file for editing. In addition, the F2 key serves to open BIOS settings along with Del.
F3. The main purpose is to invoke a search, whether it is a search in Explorer, on a web page in a browser, or in an open document. The combination Ctrl + F works in the same way.
F4 - Varies from program to program. In some browsers and Windows Explorer, moves the cursor to the address bar while displaying history.
F5. A universal purpose is the refresh function. Updates the content of browsers, control consoles, explorer, file managers and many other programs.
A useful combination when working with a browser is Ctrl + F5. It allows you to refresh the page without using the cache.
The F6 has no standard feature. In browsers, the action is similar to F4, but the history is not displayed. Often used to switch between controls like the Tab key.
F7, F8, F9 - the purpose depends on a specific program or OS. When Windows starts, pressing F8 brings up a menu with boot options, and F9 activates System Restore.
F10 is a menu call, not the only one, but a fairly frequent assignment, and the combination Shift + F10 calls up a context menu, similar to the right mouse button.
F11 - The most common use is to switch between windowed and fullscreen modes.
F12 on Mac OS brings up the Dashboard by default. Also, this OS allows you to use the F9, F10, F11 keys for Expose - window management technology.
Keyboard shortcuts
Function keys are often used in combination with the so-called modifier keys - Shift, Ctrl and Alt. For example, Alt + F4 will close the application, and Ctrl + F4 will close its separate element - a tab, window, file.
In addition, on laptops, you can find the Fn button, in combination with a functional keyboard, it can control sound, screen brightness or contrast, power for Wi-Fi and Bluetooth radio modules, disable the touchpad and much more. The exact combinations depend on the laptop manufacturer and model.
