I did some research on SharePoint Databases and how are they providing datas to SharePoint sites?. Here i am come up with some details of Databases used in SharePoint.

Database Name Description Availablity
This is the Central Admin Content database, is used to store all WSS 3.0 / MOSS content. WSS3.0, MOSS 
SharePoint_Config The configuration database contains data about all the databases used, all of the IIS Web sites, Web applications, solutions, Web Part packages, site templates, and Web application and farm settings specific to SharePoint technologies, such as default quota, blocked file types, and configuration. WSS3.0, MOSS 
WSS_Search_ComputerName This database is used for the search services. It contains the information that is required for searching content.By using this database, Windows SharePoint Search services enables users to search all Web site content on the server. WSS3.0, MOSS 
WSS_Content_GUID This database contains data specific to a Web application and its site collections. It contains the content data, such as the document uploaded to a list or a library. By default, a single content database is created for each Web application. All new site collections added to a Web application use the same database WSS3.0, MOSS 
SharedServicesN_DB Each Shared Service Provider (SSP) requires a database for service-specific data. MOSS
SharedServicesN_Search_DB In addition to the SSP database, a separate database is required for frequently changing search-related data. MOSS
SharedServicesContent This database is dedicated for the shared services content. MOSS
SSO This database stores the settings and account information for single sign-on. MOSS

For more informations, visit Windows SharePoint Services 3.0 ,  Office SharePoint Server.