The first picture on the left is where the video card is located inside the computer, it is standing on it's side so you will not see much from this angle.
The right image is a board shot of my Video card . That is some complex circuitry. Lucky for us it is very easy to setup
Click to enlarge the images.

What does it do?

The Video card allows you to see. The monitor is plugged into the video card so the video card will be able to produce a image that will be displayed on the screen.

That is the basic purpose of a video card. There are many type of video cards but that will be discussed in another topic, Upgrading.

Next : The RAM