The easiest concepts to grasp in the CS165 class were: conscious cache algorithms, concurrency control, column-store and hybrid systems, hardware and software co-design, shared nothing architectures, introduction to modern data systems and main memory systems (Catalogs, 2007). It was hard to grasp traditional and seminal concepts, adaptive indexing, scientific data management, stream processing and key-value stores. This class increased my creative thinking and problem-solving skills on data systems. I liked designing modern data systems, implementing them, and programming in different languages. Complex data should be simplified for easier analyses. The SQL and UNIX queries should be simplified for easy understanding.