Many small appliances are powered by electricity. The appliance may use a permanently attached cord which is plugged into a wall outlet or a detachable cord. The appliance may have a cord storage feature. A few hand-held appliances use batteries, which may be disposable or rechargeable. Some appliances consist of an electrical motor upon which is mounted various attachments so as to constitute several individual appliances, such as a blender, a food processor, or a juicer. Many stand mixers, while functioning primarily as a mixer, have attachments which can perform additional functions.

A few gas-powered appliances exist for use in situations where electricity is not expected to be available, but these are typically larger and not as portable as most small appliances. Items that perform the same function as small appliances but are hand powered are generally referred to as tools or gadgets, for example a hand-powered meat grinder.

Some small appliances perform the same or similar function as their larger counterparts. For example, a toaster oven is a small appliance that performs a similar function as an oven. Small appliances often have a home version and a commercial version. The commercial, or industrial, version is designed to be used nearly continuously in a restaurant or other similar setting. Commercial appliances are typically connected to a more powerful electrical outlet, are larger and stronger, have more user-serviceable parts, and cost significantly more.

Small appliances can be very inexpensive, such as a basic can opener or coffee maker which may cost only a few U.S. dollars, or very expensive, such as an elaborate espresso maker, which may cost several thousand U.S. dollars. Most homes contain several cheaper home appliances, with perhaps a few more expensive appliances, such as a high-end microwave oven or mixer.