TITLE: What does "toy-contour" mean?
QUESTION [9 upvotes]: When I reading Complex Analysis written by Stein and Shakarchi. In Chapter 2, he had introduced a notion "toy contour "without explaining. what does this exactly mean?

REPLY [3 votes]: Taken from page 40 of the book,

Although presented somewhat unrigorously, toy contours are essentially always clear in use.