Suggest some SAS support website technical references and also SAS-hosted documentation, also available on the SAS support site at
http://support.sas.com/ on this topic / post.
Typically a FUNCTION provides a defined purpose/use to perform some type of task, calculation, data-manipulation, or otherwise utility execution in the SAS environment. And the MACRO FACILITY is a language used within the SAS environment, where SAS programmers can exploit coding techniques to perform executed-once or executed-repetitively task processes to address a particular programming activity or to generate some result with SAS.
Scott Barry
SBBWorks, Inc.
Suggested Google advanced search arguments, this topic / post:
function introduction site:sas.com
macro introduction site:sas.com