My Basic Knowledge: Oracle Tablespaces and Data Files

Databases, tablespaces, and data files are closely related but have important differences.

An Oracle database consists of one or more logical storage units—its tablespaces—that collectively store all the database’s data.
Each tablespace in an Oracle database consists of one or more data files, which are physical structures that conform to the operating system on which the Oracle software runs.
A database’s data is collectively stored in the data files that constitute each tablespace of the database. An Oracle database must have a minimum of two tablespaces (the required SYSTEM and SYSAUX tablespaces), each with one data file. Another database can have three tablespaces, each consisting of two data files (for a total of six data files). A single database can have as many as 65,534 data files. If a tablespace consists for its lifetime of exactly one (and only one) data file, it is defined as a bigfile tablespace. This is a special case that is useful for data warehouse applications.
A tempfile is a file that belongs to a temporary tablespace; it is created with the TEMPFILE option. Temporary tablespaces cannot contain permanent database objects such as tables, and are typically used for sorting.