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10/5/2009
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Z
The third dimension axis in a 3-dimensional graph (the 2-dimensional axes being x and y).
Software for a PC (application, file or programme) can be compressed in size to facilitate sending over a network or putting on a disc/CD. The process of compressing it is often called zipping and decompressing it is called unzipping. This is one of those proprietary words that has crept into general usage, e.g. An Apple Mac user will use Stuffit but still refer to zipping.
A two-way wireless communications technology for control and sensor applications at up to 250 kbit/s, typically for remotely controlling devices such as for lighting, air-conditioning or security and using a feedback path for status information. It has very low-power consumption and hence low-power output. ZigBee defines application and security layers above the PHY and MAC layers of the IEEE 802.15.4 standard. Several bands are specified, only one of which (the 2.4Ghz band) is common to the USA and Europe and permits the full 250kbit/s rate.
Often used in telecommunications in its general sense, as in a zone of a building. It can define a part of a network, notably a LAN, and it used to be used in the UK to describe an area of the country covered by a Zone Switching Centre.
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