Once you have an account, you add the "Pin It" button to your browser so that whenever you find an image you like you just click "Pin It". A window pops up with all of the available images on the page, you choose which one you want, select one of your boards, write a description and the image is pinned to the site. It shows the link to where you got it too so you don't have to worry about giving credit. Plus you'll be able to easily find the site where you first saw it.
Here is my dashboard with all of my "boards"
My "Inspiration" Board
My "For the Home" Board