When a file has more than one version, you can compare any two of them.
On your project page
Open the file's Versions list and choose Compare versions. Pick the two versions you want:
- Images and PDF pages appear next to each other. For documents, turning the page turns both.
- Videos play side by side, together.
For your client
On the review page, a file with an earlier version your client has seen shows Compare with that version, so they can check the change for themselves. They can only compare versions that were sent to them.