desktop manager ip modem?

Just hooked up my phone to the computer and open up DM and notice IP modem set up.
Could some one tell me a little about it, I think it is where i can use my computer and access the internet using the phone as a modem.

If so is there a charge for doing it?
I have Verizon.

You can use this to get the internet on your computer. You do need to have tethering on your Verizon plan.