In SAS, procedures use engines
to access data. Characteristics of these engines vary; generally,
they enable SAS procedures to access a data library in a particular
way. Engines can specify the expected format for the SAS data file,
the type of read or write activity that can occur in SAS data files,
and so on. In most cases, you use the default engine for the current
SAS version and do not need to specify an engine.
For more information, see SAS Engines in SAS Language Reference: Concepts.