If you are not using OMF, you will need to manage datafiles yourself. The database will create or reuse one or more datafiles in the sizes and locations that you specify whenever you create a tablespace. A datafile belongs to only one tablespace and only one database at a time. Temp files are a special variety of datafile that are used in temporary tablespaces. When the database creates or reuses a datafile, the operating system file is allocated and initialized—filled with a regular pattern of mostly binary zeros. This initialization will not occur with temp files.
Operations that you may need to perform on datafiles include the following:
Taking them offline or online
Moving (renaming) them
Recovering them ...