When someone calls your iPhone, you'll know it; three out of your five senses are alerted. Depending on how you've set up your iPhone, you'll hear a ring, feel vibration, and see the caller's name and photo fill that giant iPhone screen. (Scent and taste will have to wait until iPhone 2.0.)
How you answer depends on what's happening at the time:
If you're using the iPhone, tap the green Answer button. Tap End Call when you both have said enough.
If the iPhone is asleep or locked, the screen lights up and says, "slide to answer." If you slide your finger as indicated by the arrow, you simultaneously unlock the phone and answer the call.
If you're wearing earbuds, the music nicely fades out and then pauses; you hear the ring both through the phone's speaker and through your earbuds. Answer by squeezing the clicker on the right earbud cord, or by using either of the methods described above.
When the call is over, you can click again to hang up—or just wait until the other guy hangs up. Either way, the music will fade in again and resume from precisely the spot where you were so rudely interrupted.
incoming calls pause and fade video playback ...