The underlying rules governing email transmission are highly standardized, but there are a large number of different software programs that can be used to read email. It's quite possible that the message you send won't look at all the same when displayed on your correspondent's screen. You therefore have to be careful about how you present your text. This section will discuss the problems that may arise from a mismatch between the sending and receiving software, and show how to avoid them.
Some email reading software only understands plain text.
Italics, bold, and color changes will show up as control sequences in the text. Hey, I loved the presentation you gave to Jack this morning. Web documents are particularly difficult to read with older email programs. This allowed some free space for error correction - something important when computers were calling each other with modems. However, the net is a different place now.