As I stare at the computer screen contemplating my next blog, the question "What makes teaching so difficult?" keeps running through my head.  How difficult can it be to tell or show someone else what you know?  Theoretically, it should be easy.  Use clear, concise language, concrete examples and voila!  Right? Unfortunately, it is not that easy.  Teaching, and learning for that matter, is challenging because of the many variables that come into play.  One of those important variables is the personality that each of us brings to the table.  As an article from the ASTD website indicates, personality, and the understanding thereof, is one of the keys to success in the learning and teaching industry. Many instructors, in both business and education sectors, will begin their courses with a personality assessment of their students.  Understanding who you are working with and affording them the chance to understand who they are in the classroom culture is essential.  Certainly the impact of each individual's personality can contribute to the challenge of teaching but is can also be one of the most rewarding parts.