$1M vs. $1MM...what's the difference?

In going through magazine articles involving large numbers, I was wondering if there was a difference between $1M (one million dollars) and $1MM

Actually, $1MM is a million dollars and $1M is a thousand dollars. Let me see if I can find a thread from a day or so ago…

Here ya’ go.

Dear me, my first post in over a year and I ask a question answered days earlier. I must do some research before I address the teeming millions once again. Thanks for the tip, Ringo.

I knew this sounded familiar. Since this has been discussed so recently, I’ll close this thread and direct further comment to the earlier thread, linked to above.