.txt

.txt is a filename extension for files consisting of text usually contain very little formatting (e.g., no boldface or italics). The precise definition of the .txt format is not specified, but typically matches the format accepted by the system terminal or simple text editor. Files with the .txt extension can easily be read or opened by any program that reads text and, for that reason, are considered universal (or platform independent).

The ASCII character set is the most common format for English-language text files, and is generally assumed to be the default file format in many situations.