A database contains and may collect information. The type of information in a database depends on the purpose of the database.
For example a web site might hold a wealth of articles. These articles may be input to a database to allow users to search the articles for specific subjects. It might contain links that are organized by subject matter or category.
In the case of an e-commerce web sites, databases may be used to serve up products, providing size, color, styles and other product variations along with descriptions of the products. Another database (or a select tables in the original database) may collect personal data such as name, address, phone number, email address, product ordered, shipping information, etc. when those items are purchased. In this case the database can provide information and accept new information to the database.
The most common types of databases are Microsoft Access, MySQL or SQL. However, there are a myriad of database languages. Staying with the most common ones ensures common programming languages such as ASP, PHP and Cold Fusion (CF) can talk to the database and extract information.
The choice between Access, MySQL and SQL depends on the use of the database, how often it may be queried and how much information it may contain. Access is best for very small databases that will not have numerous users at the same time. MySQL allows for more information and users, SQL is the "big daddy" of databases.
Databases enable programmers to write queries to the database so that users find matches for the information they seek.

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