What is instructional design?
Instructional design is the process by which principles of training and instruction are used to create instructional materials.
What is instruction?
Instruction is producing and delivering information and activities that target specific learning goals. In a system context, instruction is the gap between what the students know now, and what they will need to know after the system or new process is implemented:
WHAT I NEED TO KNOW - WHAT I ALREADY KNOW=