Insert Key

There is no 'insert' key with a function similar to that in Windows. If you are looking for the insert/overwrite toggle, you won't find that sort of text entry in Mac apps (and it looks like it's even been eliminated from MS Office 2008 for Mac, though is was supported in MS Office 2004 by clicking a toggle in the status bar at the bottom of a document window). The Mac OS use only 'insert' mode, so to overwrite you must select the text you want to overwrite then start typing.

If you are looking for a keyboard mapping of the insert key for use +in Windows+ (e.g. if you are running Boot Camp), there is no mapped key combo on the MBP internal keyboard, but external keyboards do provide that function. It's fn+return on the Apple Wireless Keyboard and fn+enter on the Apple Ultra-thin (USB) Keyboard.

See these kbase articles:

http://support.apple.com/kb/HT1167
http://support.apple.com/kb/HT1171
http://support.apple.com/kb/HT1216

There is really no Insert key available on the MacBook family, however, a number of people have reported that they can use this feature by the _fn + return_ shortcut. Yet most Bootcamp users claim that the _fn + control + m_ or even _fn + m_ combinations can work. I do have the new MacBook Pro, yet I haven't come across the Insert Key so far, thus I am new to the different calibrations. If you may, can you try the shortcuts I mentioned and see which one works for you on a test document or any preferred example?

I did have a look at those articles before I posted my previous message, yet I did some calibrating research on my own and found out that some users were capable of acquiring the shortcut to the Insert key (or its equivalent from Windows to a Mac notebook). This is simply to say that the mapping of the "insert" key has not been considered by default means, but can be done (most likely through bootcamp keyboard calibration, though like neuroanatomist says, Mac apps do not require that sort of function... so I'm assuming you need it for a bootcamp/windows-related issues).