The first type of aquarium that most people use is the small "goldfish" bowl type of aquarium. These bowls come in several different shapes and sizes, and are generally used for a very small number of fish, usually of the same species.
Small bowls are very useful as starters when it comes to aquariums, because they help introduce new fish owners to the basic needs of their pets. The bowls need to be cleaned out on a regular basis, the fish fed, and so on. This type of aquarium gets fish owners off on the right foot by helping them form good habits that they will need in order to keep the larger and more exotic types of fish found in large aquariums alive. They are great for children or people on the go, maybe young professionals who do not spend a lot of time at home.
Many aquarium enthusiasts use small bowls as a type of experimental fish display case. The size of the bowl means that you can keep the aquarium decorations to a minimum, and that means less clean up is needed as well as less expense. Just a bit of gravel and a plant or two are often enough to create a realistic and decorative environment for your fish. This is just like any other hobby. Those interested in cars wouldn't rush out and buy everything down to the front auto plate before finding out more about car restoration. (If you do need some auto supplies, we definitely recommend, Wheelsauto.com however!)
Small bowls are also very useful when it comes to more aggressive species of fish. A good example is the very popular betta fish. Also known as Siamese fighting fish, these beautiful fish will kill any other fish in the tank with them. A small bowl is an ideal environment for bettas; it not only offers them enough room to move, it allows them to be displayed to maximum effect.
Speaking of display, a small bowl does not mean that you have to forgo the necessities. Small overhead lights are the perfect way to complement your small bowl aquarium display. You can even purchase small bowl starter kits that include lights. Most of the time, these lights have a base at the bottom of the bowl but shine over the top, emulating the sun. They imitate natural light, so your fish still feel comfortable while you gaze at them. While you would probably like to give your fish a home that's equivalent to you getting a fancy condo, that's not always possible for first time fish owners.
Small bowl aquariums are great ways to start out, no matter what age you are at. They fit almost anywhere and you can decorate them as you please.