Editing Text mode (section)

{{short description|Computer display mode based on characters}}
{{refimprove|date=October 2010}}

'''Text mode''' is a [[computer monitor|computer display]] mode in which content is internally represented on a computer screen in terms of [[character (computing)|character]]s rather than individual [[pixel]]s. Typically, the screen consists of a uniform [[regular grid|rectangular grid]] of ''character cells'', each of which contains one of the characters of a [[character set]]; at the same time, contrasted to [[graphics mode]] or other kinds of [[computer graphics]] modes.

Text mode applications communicate with the user by using [[command-line interface]]s and [[Text-based user interface|text user interfaces]]. Many character sets used in text mode applications also contain a limited set of predefined semi-graphical characters usable for [[box-drawing character|drawing boxes]] and other rudimentary graphics, which can be used to highlight the content or to simulate [[Graphical widget|widget]] or control interface objects found in [[Graphical user interface|GUI]] programs. A typical example is the [[IBM]] [[code page 437]] character set.

An important characteristic of text mode programs is that they assume [[monospaced font]]s, where every character has the same width on screen, which allows them to easily maintain the vertical alignment when displaying semi-graphical characters. This was an analogy of early mechanical printers which had fixed pitch. This way, the output seen on the screen could be sent directly to the printer maintaining the same format.

Depending on the environment, the [[framebuffer|screen buffer]] can be [[Memory-mapped I/O|directly addressable]]. Programs that display output on remote [[computer terminal|video terminal]]s must issue special [[Escape sequence|control sequences]] to manipulate the screen buffer. The most popular standards for such control sequences are [[ANSI escape code|ANSI]] and [[VT100]].

Programs accessing the screen buffer through control sequences may lose synchronization with the actual display so that many text mode programs have a ''redisplay everything'' command, often associated with the {{keypress|Ctrl|L}} key combination.