This page explains how to close a program.
Their are a number of ways to close or shut down a program. It is not really necessary to know everyone of these ways, since they all accomplish exactly the same thing.
The easiest way to close a Windows program is to click the in the top right corner. This method doesn't work if your computer is frozen or if there is no X in the top corner.
Some programs, particularly DOS programs running in full screen mode, have no in the top corner and frequently they do not have a mouse cursor either. The best way to close programs like this is a follows:
If your computer is frozen and the above methods do not work press ctrl+alt+del and then if an End Task Window appears, highlight the program you want to shut down and then click End Task. If this approach doesn't work when your computer is frozen, turn off your computer and then restart it.