文本文档一般指只有字符原生编码构成的二进制计算机文档，与富文本相比，其不包含字样样式的控制元素，能够被最简单的文本编辑器直接读取。

由于结构简单，文本文档被广泛用于记录信息。它能够避免其它文档格式遇到的一些问题。此外，当文本文档中的部分信息出现错误时，往往能够比较容易的从错误中恢复出来，并继续处理其余的内容。文本文档的一个缺点是，它的熵往往较低，也就是说，其实本可以用更小的存储空间记录这些信息。

A text file (sometimes spelled "textfile": an old alternative name is "flatfile") is a kind of computer file that is structured as a sequence of lines of electronic text. A text file exists within a computer file system. The end of a text file is often denoted by placing one or more special characters, known as an end-of-file marker, after the last line in a text file. However, on some popular operating systems such as Windows or Linux, text files do not contain any special EOF character.