Hang On Back (HOB) filters are usually the first filters a budding aquarist will graduate to from having a sponge filter or an internal filter. They are designed to "hang on to the back" of the tank, mostly used on the side glass pane to ensure a good water flow.
These filters are easy to use and clean,with adequate space for filter media. Most come with adjustable flow controls. You will find some good choices here in this section.