Microsoft Word?

REC is a shortcut button for recording a Macro. A Macro is a recording of tasks that you use repeatedly. You will find the Macro option under the Tools menu

TRK is a shortcut button for Track Changes, which is also found under the Tools menu. You can use this to mark changes you make to a document so that they show on screen.

EXT is for extending or shortening a selection (highlight) you have made in your document. Select some text by clicking and dragging over it, then double-click on the EXT button and you can place your cursor at the point you want the selection to end. (Don’t forget to turn it off by double-clicking again on it when you are finished).

OVR is a shortcut button for the Overtype mode. Instead of inserting text at an insertion point it would overtype or replace the text coming after the cursor.

All of these buttons are activated by double-clicking on them and you double-click again to turn them off.

rec is record your voice...but u need headset. and i love trk if u type something and then press trk anything u add it will turn up in a different color and if u change somthing it will turn a different color and it will tell u what it was. good for editing. experiment with it. i havent used the others.

If you hover your mouse over each one, it'll tell you.