"A database is a collection of information stored in a computer in a systematic way, such that a computer program can consult it to answer questions."
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Databases are an integral part of almost any system in the world of computing today. As the expectations of users and the complexity of applications continue to increase, any decent application system would need a database to store and manage information.
Databases have grown larger and more powerful as technology advances. It is now common to have databases which are terabytes in size and hosted on multiple servers