Install these drivers on your computer!

Enable Settings → Applications → Development → USB debugging on your phone after you install the drivers.

Windows 7/Vista/XP (core package): 32-bit / 64-bit

Some phones require supplementary Windows-only drivers (first install the core package): Samsung / LG

Mac OS X 10.4+ (up to 10.7): universal Intel/PowerPC

Ubuntu 10.4+: i386 / amd64

Fedora 13+: i686 / x86_64