Every version control tool provides a way to include a log message (a comment) when committing changes to the repository. This comment is important. If we consistently use good comments when we commit, our repository’s history contains not only every change we have ever made, but it also contains an explanation of why those changes happened. These kinds of records can be invaluable later as we forget things.

I believe developers should be encouraged to enter log messages which are as long as necessary to explain what is going on. Don’t just type “minor change”. Tell us what the minor change was. Don’t just tell us “fixed bug 1234”. Tell us what bug 1234 is and tell us a little bit about the changes that were necessary to fix it.