MH commands like mhl (which show can use to format messages), repl -filter, forw -filter, and scan read special MH formatting instructions. These let you change the appearance of messages -- including which fields from the header you see and in what order, how long the lines will be, and more. If you're customizing MH, you'll want to understand MH formatting.
This chapter takes you through many ways that you can use MH formatting. It will help you learn the principles with lots of examples. The later examples go into depth. Many of the examples show practical formatting that you might want to use every day.
The Sections Summary of mhl and Summary of MH Format Strings are summaries of this chapter's two major topics. The sections are adapted from the MH 6.8.3 mhl(1) and mh-format(5) manual pages.
NOTE: for users of the online version of this book: This chapter has a lot of examples followed by long explanations. To avoid jumping between the example and its explanation, it's a good idea to open a new browser window to show an example. (Check your browser's menu for a command like New Web Browser or Open in New Window). Then, use the original browser to read the explanation while you view the example in the second browser window.