When collaborating on a set of definitions, you can review the history of the definition, including who made each change, when the change was made, and what the definition was at each version.
To access definition history, navigate to Definitions > select the page for the type of definition you want to see the history of (Events, Segments, or Properties). Search for and click on the definition to open the definition details view, then scroll down to the history section. Here you will see a full record with timestamps for each time the definition was modified.
You can also filter for events or segments that were updated in the last 7 days via the Modified filter.
In the history section, click on any version link to view details about that version. You can also revert to a previous version by clicking on the version you would like to revert to and clicking Restore Version.
When making changes to events or segments, you can also leave a note to provide more context on what the change is and why you made it.