The Activity History related list of a record displays all completed tasks, logged phone calls, saved interaction logs, expired events, outbound email, mass email, email added from Microsoft Outlook®, and merged documents for the record and its associated records.
Activity History Related List

The Activity History related list, on any record that has one (Accounts, Contacts, Matters, etc.) can be viewed or modified.
From the Activity History related list:
- Choose edit next to the Activity you choose to modify.
- Click on the subject of the Activity you want to view.