Information
Types of light bulb
Incandescent
This is the standard light bulb we have been using for many years, a glass bulb with a filament in it. They are usually white, the glass that is, although they are also available with clear glass. The clear glass versions may be tinted with red for use in electric fires, or blue for more of a similarity to the colour of daylight.
Fluorescent
These lights are usually in the form of long tubes, used for ceiling lighting in offices, shops and in the home, in kitchens. They are sometimes called striplights.
There have been a few attempts to use them in other applications in slightly different forms, the most likely one you will see is a circular version of the tube, used in round flat ceiling lights.
Compact Fluorescent
These are the modern energy saving bulbs, most often in the form of a spiral of thin fluorescent tube, usually slightly larger than a standard incandescent bulb. They use much less electricity than an ordinary bulb and they last a lot longer.
The spiral may be enclosed in a glass bulb, to make them look more like an ordinary bulb, and to diffuse the sometimes harsh light of the fluorescent tube, giving a softer light more acceptable in the home.
LEDs
Light emitting diodes are the modern electronic versions of light bulbs. They are based on the ability of small electronic components called diodes to emit light when an electric current is passed through them.
They use only a fraction of the energy used by traditional incandescent bulbs and also considerably less than the more recent compact fluorescent, or energy saving bulbs. They also light up instantly, but produce only a small amount of light individually, so you will usually find several LEDs used together in a light fitting, or even in a torch, etc, to produce enought light to be effective.
Light Bulb Fittings
Bayonet Cap (BC)
This is the most common type of fitting found in the UK. It is inserted into the socket, pushed in and turned a little to the right, then released. This is the same way a bayonet is fitted to a rifle, hence the name.
Small Bayonet Cap (SBC)
This is just a smaller version of the standard bayonet cap fitting, used on the small bulbs for use where space is limited.
Edison Screw (ES)
The Edison Screw fitting has been seen more and more in the UK in recent years. The bulb is screwed clockwise into the socket, with screw threads to locate it and hold it firmly.
Small Edison Screw (SES)
This is just a smaller version of the standard Edison Screw, for smaller bulbs used in more compact locations.