If there is no such information, create this section and leave it blank for future use. It's a useful thing to have when you're talking with engineers of previous versions of the module. And it's a very useful thing to have if you're tracking down mysterious bugs late in the development cycle. Always add a line about every change you make, even if it is short. Finally, use meaningful comments throughout the body of the code.
Meaningful comments continue the guidelines just described.
They tell the reader why a section of code is there, what its purpose is, and how it relates to other code . Implementing these coding guidelines may take you a little longer when you first start using them. You'll quickly see the payoff for the time you spent, however. This is especially true at the end of a project, when schedules are tight and every minute of debugging is a minute too long. The methods I've presented will reduce the number of bugs you have, and make it easier to find and fix bugs that do exist.