Database

From Wikipedia, the free encyclopedia.
http://en.wikipedia.org/wiki/Database

A database is an information set with a regular structure.

Any set of information may be called a database. Nevertheless, the term was invented to refer to computerised data, and is used almost exclusively in computing. Sometimes it is used to refer to not yet computerised data, but usually in the process of planning its possible computerisation.

Software created to manage generalised databases is usually called a database management system or DBMS. Several software architectures are possible: For smaller single user databases often all functions are managed by one program. In larger and multiple user databases usually a number of programs are involved and most commonly a client-server architecture is adopted.

The DBMS front-end (i.e., the clients) is concerned mainly with data entry, enquiry and reporting. The back-end (i.e. the server) is the set of programs that actually control data storage, responding to requests from the frontend. Searching and sorting is usually performed by the server. There are a wide variety of database implementations, from simple tables stored in a single file each to very large databases with many millions of records, stored in rooms full of disk drives or other peripheral electronic storage devices.

Databases resembling modern versions were first developed in the 1960s. A pioneer in the field was Charles Bachman. Two key data models arose at this time: the network model (developed by CODASYL) followed by the hierarchical model (as implemented in IMS). These were later usurped by the relational model, which was contemporary with the so-called flat model designed for very small tasks. Another contemporary of the relational model is the object-oriented database (OODB).

While the relational model is based on set theory, one proposed modification suggests fuzzy set theory (based on fuzzy logic) as an alternative.

More information at:
http://en.wikipedia.org/wiki/Database