The summary + description format in Git commits is a matter of (good) convention:
- The summary should be 70 characters or less
- An optional longer description can follow, after an empty line after the summary
The command line equivalent of entering "brief summary" as summary and "doing this and that" as description:
git commit -m 'brief summary
doing this and that'
Or on a single line in bash
:
git commit -m 'brief summary'$'\n\n''doing this and that'