Monday, May 13, 2002		Bits & Bytes

BTU: Short for British thermal unit, an English standard unit of energy. One Btu is equal to the amount of heat required to raise the temperature of one pound of liquid water by 1 degree Fahrenheit at its maximum density, which occurs at a temperature of 39.1 degrees Fahrenheit. One Btu is equal to approximately 251.9 calories or 1055 joules. The heat output of computer devices is often expressed in Btus.

Server appliance: Also called an appliance server, a specialised server that is designed for ease of installation and maintenance. Server appliances have their hardware and software bundled in the product, so all applications are pre-installed. The appliance is plugged into an existing network and can begin working almost immediately, with little configuration. It is designed to run with little or no support.

Quantum dot: A nano-scale crystalline structure made from cadmium selenide that absorbs white light and then re-emits it a couple of nanoseconds later in a specific colour. The quantum dot has been around since the 1980s when scientists were looking into the technology as a way to build nano-scale computing applications where light is used to process information. More recently, however, the technology is being used in medicine. The crystals are one ten-millionth of an inch in size and can be dissolved in water. When illuminated, they act as molecule-sized LEDs and can be used as probes to track antibodies, viruses, proteins, or DNA within the human body.