For windows.

Select/Copy the rich text to the windows clipboard.

Paste the copied text into a non rich text enabled editor e.g. notepad.

Plain text has no extra atribut like font, bold... etc.

Rich text has those extra atribut.

Plain text has only the text of the document, without any formatting. "Rich text" also includes information about the document formatting, such as font, size, bold, italics, margins and so-on.

Most word processing programs these days will read "RTF" - Rich Text Format - and format the document for you.

rich text &.rtf extensions rich text &.rtf extensions

Two examples are Text (.txt) and Rich Text (.rtf)