A text editor is a computer program that lets a user enter, change, store, and usually print text (characters and numbers, each encoded by the computer and its input and output devices, arranged to have meaning to users or to other programs). Typically, a text editor provides an "empty" display screen (or "scrollable page") with a fixed-line length and visible line numbers. You can then fill the lines in with text, line by line. A special command line lets you move to a new page, scroll forward or backward, make global changes in the document, save the document, and perform other actions. After saving a document, you can then print it or display it. Before printing or displaying it, you may be able to format it for some specific output device or class of output device. Text editors can be used to enter program language source statements or to create documents such as technical manuals.
A popular text editor in IBM's large or mainframe computers is called XEDIT. In UNIX systems, the two most commonly used text editors are Emacs and vi . In personal computer systems, word processor s are more common than text editors. However, there are variations of mainframe and UNIX text editors that are provided for use on personal computers. An example is KEDIT, which is basically XEDIT for Windows.