I’m Ahmed Khattab  jr sap abab developer with very good knowledge about abap Concepts such as :-

1- Reports (classical, Interactive,ALV)

2- ABAP Dictionary (creating DB tables, views, Domains for data elements, search help, lock objects, Data types like global structure and internal tables)

3-Modularization Techniques (function modules, Subroutines, Include Programs and Macros)

4- ABAP open and native SQL

5- Internal Tables and Work Areas and operations on it.

6- Dialog /Screen programming -module pool programming -(design Screens with screen painter and Menu painter and create tcode )

7- very good understanding ABAP Debugger

8- Enhancements (user exit, customer exits and BADIs)

9- BDC Recording

10- LSMW

11- BAPIs and rfc

12-Adobe Forms

13- IDOC