Fibre optics is the transmission of information in the form of a light signal through optical fibers. Fibre optic technology can support transmission rates of over two billion light pulses per second, carrying information at speeds that are not possible over copper wires. For example, a 24-fibre cable can carry 750,000 phone conversations simultaneously. By comparison, a 200-pair copper telephone cable will transmit 10,000 conversations. Optical fibres are made from glass or plastic and range from tight buffer and armored products for military applications to loose tube and hybrid cables for local area and wide area networks (LAN and WAN respectively). Other typical applications include telephone systems, community Antenna Television (CATV), control systems and high-definition television (HDTV). Air blown fibre, another form of optical fibre technology, is an advanced system that is also ideal for LANs and campus applications. Fibre optic technology offers high bandwidth and protection from electromagnetic interference, eavesdropping and radioactivity.