Both computing and mathematics are devoted to studying abstraction. Mathematics is the science of abstraction, and computing is abstraction engineering. Abstractions in mathematics include sets, graphs, functions, algebras, and spaces. In computing, abstractions typically include floating-point numbers, stacks, lists, channels, processes, protocols, instruction sets, type systems, and programming languages. The "computer" is itself a key abstraction since we use it to represent and manipulate other abstractions. We outline how the perspective of computing as abstraction engineering yields concrete problem-solving wisdom.