And I want to remind you, that block of code is a set of instructions, the same set of instructions that are going to be done each time through the loop.

我想提醒大家,这块代码是一个指令集,一个每次循环都会被执行的相同指令集,会变化的仅仅是变量的值。

麻省理工公开课 - 计算机科学及编程导论课程节选