As instructors, we make hundreds of decisions throughout a semester as we interact with our students, explain concepts and procedures, or assess their knowledge and skills. To help us make choices - among other important factors - understanding the characteristics and needs of learners is fundamental to designing effective and efficient learning experiences. For example, as parents can tell you, there is quite the difference on how one would explain a certain concept to a 5-year-old versus someone who is in his late thirties! In addition to age, other characteristics play important parts, such as location, language, background, etc. Hence, familiarity of fundamental facts pertaining to the learner population can significantly support the learning effectiveness, efficiency, as well as the engagement. Over the past decade, the learner population of ASU Online has seen significant growth. What started with a few hundred enrolled students at the beginning of the decade has grown exponenti...