Instructional design is influenced by how users learn, which is affected by various factors. These factors include meaningfulness, serial position effects, practice effects, transfer effects, interference effects, organization effects, levels-of-processing effects, state-dependent effects, mnemonic effects, abstraction effects, levels effects, prior knowledge effects, inference effects, student misconception effects, text organization effects, and mathemagenic effects. All of these learning factors must be considered when designing effective instructional materials and activities.