Fluorescent lamps have been around for a long time and are generally regarded as being the original energy saving lamps. Although they are now available in a vast range of different shapes and sizes, they all still work along the same principles as the familiar tube lamps, where a mercury vapour discharge energises a fluorescent coating applied to the inside surface of the glass. Larger fluorescent lamps normally require a starter and ballast, more usually being an electronic control device. The huge rise in popularity of fluorescent lamps has come about largely due to the development of the compact CFL versions, offering huge energy savings compared to the earlier tungsten filament incandescent lamps. Although a bewilderingly large range of different types exists, the correct bulb can normally be selected by simply choosing the correct shape, size, socket-type and power. For some applications, especially those requiring very small bulbs, halogen lamps or LED lamps are the obvious choice - the latter in particular making significant inroads into the domestic lighting market, being available in a vast range of different bulb types. Fluorescent lamps, however, continue to hold a large market share and look set to continue to do so.