startsection section 1 0mm-3.5ex plus -1ex minus -.2ex0.7ex plus.2exFunctions

A few times now, we have mentioned ``all the things functions are good for.'' By now, you might be wondering what exactly those things are. Here are some of them:

• Giving a name to a sequence of statements makes your program easier to read and debug.

• Dividing a long program into functions allows you to separate parts of the program, debug them in isolation, and then compose them into a whole.

• Functions facilitate both recursion and iteration.

• Well-designed functions are often useful for many programs. Once you write and debug one, you can reuse it.