What does code P0442 mean?

I have a 2002 Ford Mustang and today my cars service engine light came on and i got a scanner and the only code that came up was P0442. What does this mean? What are the solutions to fixing this problem? Is it safe to drive it for a few more days since I'm very busy during week days and I won;t have time to take it to the mechanic until saturday (in case i can't fix the problem myself? How much would a repair cost?

Basically this is a small leak in the Evaporative Emission system.
In short the car applies 2-3 psi into the fuel system to route fumes to a charcoal canister. This removes pollutants. I have never seen this code affect the driveabilty of the car, nor cause any extensive repairs. It is hard to diagnose these small leaks. A diagnostic piece of equipment called a smoke machine is used to diagnose the leak. Small leaks are Really hard to find and you could spend a lot of money on the diagnostics.

Replace the fuel cap first, and some parts stores have the ability to erase the codes. You can then see if the new cap solves the leak. (it often does). I foyu don't get the code cleared, if the new cap solves the leak, the light will go out within a week. Goodluck

Read this post on EVAP codes

http://ricksfreeautorepairadvice.com/evaporative-emissions-system-primer/