Authority object
Is generally created by a security or system administrator based on the sensitivity of certain fields.
The authority object is checked in the ABAP program to ensure that the user has the appropriate level of authority.
AUTHORITY-CHECK statement
Lists the fields to be checked and verifies what the user is attempting to do against what the user is authorised to do.
DUMMY option
Suppresess the authority check for the field indicated
CATCH/ENDCATCH block
Allows a programmer to catch ABAP runtime errors and assign these to a SY-SUBRC value so an error can be reported in a controlled manner (rather than with a short dump).