Quick question

I'm learning PHP to create some cool web mashup site. Everything is going great so far; I've got most of the database design down.

Anyway, just one question: what is abstraction? I keep hearing this phrase get banded around a lot and when I asked my professor about he gave me a funny look like he didn't know what I was on about. You guys at /pr/ seem a lot smarter than him, can you help me out?

THANKS IN ADVANCE

Abstraction is hiding fast access to hardware in slow and less efficient software layers because the programmer is too lazy to reverse engineer the hardware, and because of our disposable society that forces everyone to upgrade everything every 2 seconds.