One of the first things that a computer does when it is switched on is to look for the operating system which is typically stored on a hard disk drive. Once the computer finds the operating system it loads part of it into memory (RAM). The process is called “booting up the computer” or simply “booting”.
Once the operating system has loaded you will typically be presented with some sort of Graphical User Interface (GUI) environment. The GUI acts as the interface between you and the computer hardware.
On a stand alone computer at start up you will be presented with a main area that shows icons and a task area, along the top, bottom or sides, which will give you access to more of the operating systems facilities. In a Microsoft Windows system the task area (taskbar) contains a Start button that when clicked on will reveal many other features of the system, many of which can be customised by the user.
On a networked computer one of the first things that you will be asked to do at start up is to log in. To do so you will enter your unique user name and password. If you enter these correctly the computer will allow you into the computer so that you can use it.
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