富文本格式（Rich Text Format）即RTF格式，又称多文本格式，是由微软公司开发的跨平台文档格式。大多数的文本处理软件都能读取和保存RTF文档。

以下RTF代码：123

在字处理软件上将显示为如下效果：

Hello!
This is some bold text.

反斜线符号（\）标志着RTF控制代码开始。代码\par表示开始新的一行，代码\b将文本以粗体显示。花括号{和}定义一个群组。上述例子中使用了一个群组来限制代码\b的作用范围。合法的RTF文档是一个以代码\rtf开始的群组。

The Rich Text Format (often abbreviated RTF) is a proprietary document file format with published specification developed by Microsoft Corporation from 1987 until 2008 for cross-platform document interchange with Microsoft products.

Most word processors are able to read and write some versions of RTF. There are several different revisions of RTF specification and portability of files will depend on what version of RTF is being used. RTF specifications were changed and published with major Microsoft Word and Office versions.