Hi, please refer the below link http://dbadiaries.com/sql-server-tempdb-whats-it-for

The tempdb is a temporary workspace for storing temporary tables, worktables that hold intermediate results during the sorting or query processing and materialized static cursors, which intern increase the performance for SQLServer.

SQL Server TempDB is a system database, automatically created when you install SQL Server So what is it used for? Well, Microsoft didn't name tempdb because they couldn't think of a suitable name. It is a temporary database which is re-created every time the SQL Server service is started and at a higher level, it could be considered to be the page file for sql server.The tempdb is a temporary workspace for storing temporary tables, worktables that hold intermediate results during the sorting or query processing and materialized static cursors, which intern increase the performance for SQLServer. SQL Server TempDB gets used Global and local temporary tables are created in here. You can't drop it You can't back it up You can't change its recovery model from simple You can't persist user created objects in the database without hassle You can't create multiple filegroups, only the PRIMARY file-group is available