Panasonic FP-D250 User Manual page 578

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D/A Converter Digital to Analog converter, Generic term for any device that changes
digital (binary) pulses into continuous wave (analog) signals. Modems, Faxes, CCDs
are D/A converters.
Data compression A way of reducing the amount of data to be transmitted by applying
one of severs techniques that reduce the number of bits needed to represent the
information. When the data is received It is decompressed into its original form.
Database Data that has been organized and structured in a disciplined fashion, so
that access to information of interest is as quick as possible. Database management
programs form the foundation for most document storage systems.
Database server A database installed as a back-end or server component of a
client-server system, which can be accessed over a LAN by one or more client, or
front-end applications through the use of query language, typically SQL. The server
part of the program is responsible for updating the records, ensuring that multiple
access is available to authorized users, protecting the data and communicating with
other servers holding relevant data. The client end of the program requests records
and then modifies them, while the server tracks records down for the client and adds
new ones.
Datagram A method of sending data in which parts of the message are sent in
random order. The recipient machine has the task of reassembling the parts in the
correct sequence. The datagram is a connectionless, single packet message or item
of data that can traverse a network at OS I Level Three, the Network Layer. It typically
does not involve end-to-end session establishment or delivery-confirmation
acknowledgment. As well as the information within the datagram, there is a destination
network address and usually a source network address.
Data link A direct serial data communications path between two devices without
intermediate switching nodes.
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