Assigning Values
In ABAP, you can assign values to data objects in both declarative and operational statements.
In declarative statements, you assign start values to data objects on declaration. To do this, you can use the VALUE parameter in the DATA, CONSTANTS, or STATICS statements (see
Creating Data Objects and Data Types).To assign values to data objects in operational statements, you can use:

Most of the operations covered in this section apply not only to internal fields in programs, but also to program parameters, table work areas, system fields, field symbols, and formal parameters, and even constants and literals in cases where the data object is not meant to be changed. When discussing operations on fields, the reference is to fields in general, not just internal fields.