What is DVI and why do I need it?

[theplanb]

I saw quite a number of videocards with DVI out connector..and I just assumed that it's a special thingy to connect to LCD flat pannel display unit.
But wait, I can just use VGA out to connect to the LCDs.. right?
what do i need DVI for then..

 

[JackBurton]

VGA will give you an analog signal whereas DVI outputs a digital signal. LCDs are digital so ideally you want to go digital to digital. To make a long story short, your going to get better image quality using a DVI connection instead of a VGA connection.