In most programming, you'll want to hide away implementation so that when looking at the top-most problem, it consists of a comprehensible subset of commands/code. I.e. You don't need/want to know the gory details of how a light is switched on, or a car is started. If your focus is to get the car started, you don't need to understand how the engine works, and how it needs fuel to enter the engine, how the valves work, ...