Timeline and Version are two closely related concepts in AEM. In general, Timeline represents a history log of a specific page, while Version means a "snapshot" of a page at a specific point in time. With Timeline and Version, you can perform the following actions:
- Create a version of a page, or
- Restore a page to a previous version; for example, undo a change that you made to a page.
Please note that a version of the page is created every time you publish the page.