I just got my MacBook Pro back from Apple, where I had sent it to fix the fact that it wasn't displaying video. I thought it was probably the video card (right?) but in fact they said it was the logic board. I don't know what this is.
Everything now works flawlessly, thankfully, but I'm curious: what is the logic board? What does it do, and why would it just suddenly break? What, if anything, can I do to avoid, or at least postpone, its breaking again?