SQL Server Everywhere is an "embeddded" database, used to store data on small devices, such as mobile phones, rather than require users to connect to a server to access information. Flessner said Microsoft had already developed the embedded database for internal use but will now release it as a commercial product.
Other companies, such as Oracle, IBM and Sybase, already offer embedded databases. In addition, there are several open-source options such as Sleepycat, which was recently purchased by Oracle.