A logical portion of an ORACLE database used to allocate storage for table and index data. Each tablespace corresponds to one or more physical database files. Every ORACLE database has a tablespace called SYSTEM and may have additional tablespaces. A tablespace is used to group related logical structures together. For example, tablespaces commonly group all of an application's objects to simplify certain administrative operations.
tablespace is a container for segments. A databases consists of one or more tablespaces, each made up of one or more data files. Tables and indexes are created within a particular tablespace. Make sure you do not create objects in the SYSTEM tablespace
A tablespace is a storage location where the actual data underlying database objects can be kept. It is the logical portion of the database used to allocate storage for all DBMS managed objects, such as table data, indexes, or stored procedures. Once created, a tablespace can be referred to by name when creating database objects.