Any experience with parsing changelogs?

I am preparing for an interview where I will be asked to do some work on changeLogs. I don't know what it is. I have just been given to set up a dev environment before the coding round. What's it going to be? All I know is changeLog keeps the changes which was introduced in the release versions. What could I possibly prepare with? Any leads will certainly help. I want to be prepared for the interview properly.