If you find a mistake in a file hosted on GitHub, don’t just fix it blindly - check who made the change and why. This helps you understand the context and gives you the chance to inform the contributor if a correction is needed.
GitHub makes it easy to view a file's version history, compare changes, and even see discussions around each commit.
Figure: File within GitHub UI
Figure: GitHub history button
Figure: Select a commit from the list
Figure: View the changes made
If you're working locally, you can also run the following commands to view the exact changes within the terminal.
git log -- path/to/filegit show <commit-hash>