The Work Log records checkins, checkouts, patron registration, patron editing, renewals, payments and holds placed from with the patron record for a given login.
To access the Work Log go to Administration → Local Administration → Work Log.
There are two seperate logs, Most Recently Logged Staff Actions and Most Recently Affected patrons. The Most Recently Logged Staff Actions logs the the transactions in order they have occured on the workstation. The Most Recently Affected Patrons log is a listing of the last patrons that transactions happened on.