Microsoft Office Access, previously known as Microsoft Access, is a relational database management system from Microsoft that combines the relational Microsoft Jet Database Engine with a graphical user interface and software development tools. It is a member of the 2007 Microsoft Office system.
Access can use data stored in Access/Jet, Microsoft SQL Server, Oracle, or any ODBC-compliant data container (including MySQL and PostgreSQL). Skilled software developers and data architects use it to develop application software. Relatively unskilled programmers and non-programmer "power users" can use it to build simple applications. It supports some object-oriented techniques but falls short of being a fully object-oriented development tool.
When designed correctly, Access databases can be ported (usually with some difficulty) to SQL Server or Oracle. This is important if you want to start small or develop a pilot database system and then migrate to the larger database management systems.
Fairly complex databases can be setup and running in 1/2 the time and cost of other large database systems (the simpler the database the greater the cost advantage).