If you use the Firefox web browser, you can enhance it by installing the free Adblock Plus add-on.  After you install this add-on, you can have it block all those annoying advertising images and banner ads you see on web sites.

You can install the free add-on from the Adblock Plus web site.

After you've re-started Firefox, the easy way to start blocking ads is to choose from a list of filters that will block most advertisements automatically.

You can also manually block ads by right-clicking on it, and then choosing "Adblock" from the context menu.