- General Service (A) – yellowish-white light emitted in all directions. Available clear or frosted. Types: General (A), Globe (G), Decorative (D), teardrop
- Reflector (R) – reflecting coating inside the bulb directs light forward. Flood types (FL) spread light. Spot types (SP) concentrate the light. Reflector (R) bulbs put double the amount of light on the front central area as General Service (A) of same wattage.
- Parabolic Aluminized Reflector (PAR) – those bulbs control light more precisely. They produce four times the concentrated light of General Service (A). They are used in recessed and track lighting. They are available in numerous spot and flood beam spreads. The number represents the diameter of the bulb in 1/8s of an inch.
- Multifaceted Reflector (MR) – halogen bulbs are available in two voltage types – 120V AC and 12V AC/DC.
- High-Density Discharge (HID)
- HIR – the bulb has a special coating that reflects infrared back onto the filament. Less heat escapes so the filament burns hotter and more efficiently