A named program unit is a PL/SQL code block with an name. It consists of three parts:

► Declaration Part - Defining the program unit name, calling parameters, local variables and local procedures. Declaration part is required.

► Execution Part - Defining execution logic with executable statements. Execution part is required.

► Exception Part - Defining error handling logics. Exception part is optional.

There are two types of named program units:

► Procedure - Has no return values.

► Function - Has a return value.