Cut, Copy, Paste are only active when working with text.

Clear deletes a selected time entry.

Edit Time… allows you to adjust a time entry.

Preferences… brings up the Preferences.

Start (or Stop) starts (or stops) recording time.

Pause (or Resume) pauses (or resumes) recording time.

Notes… brings up a window where you can enter notes for the selected time entry.

Set Hourly Rate… brings up a window where you set the hourly rate for the current TimeTracker document.

This menu displays all open TimeTracker windows.  A check mark (√) is next to the name of the current (frontmost) document.  To bring one of the other documents to the front, select it from this menu.