OS X Mountain Lion: View and restore past versions of documents
Many apps, including TextEdit, Pages, Numbers, and others, automatically save versions of documents as you work on them. At any time, you can browse through document versions and go back to an older version. You can also explicitly save a version.
A version is saved automatically every hour, or more frequently when you’re making many changes. A version is also saved when you open, save, duplicate, lock, rename, or revert a document.
Browse, restore, duplicate, and delete versions
- Hold the pointer to the right of the document title, click the arrow, and then choose Browse All Versions.
- Click tick marks along the timeline to browse versions.
- Do one of the following:
To restore your document to a previous version, display the version, and then click Restore.
To duplicate a version in a new document, display the version, press the Option key, and then click “Restore a Copy.”
To delete a version, display the version, hold the pointer to the right of the title, click the arrow, and then choose Delete This Version.
To delete all versions, press the Option key while holding the pointer to the right of a version’s title, click the arrow, and then choose Delete Old Versions.
To leave your document as is, without changes, click Done.
Explicitly save a version
Choose File > “Save.”
To save the document using a different filename, location, or format, hold down the Option key and choose File > “Save As.”