When you first learn EC2, you're tempted to memorize the family names and the purchase-options table. But what actually matters to a solutions architect is "why these categories exist in the first place." Once you understand why CPU-bound and memory-bound workloads demand different hardware layouts, and what economic structure lets Spot offer a 90% discount, the answer jumps out the moment you read a scenario — no memorization required.
This article covers the physical and historical background of EC2 instance design, the math behind purchase options, the internals of the Nitro hypervisor, the arrival of Graviton ARM, and how Placement Groups connect to distributed-systems theory.