LISP code should be indented in a way which reveals its structure. Some editors, such as emacs, will automatically indent LISP code in a reasonable way. If your editor will not do this, follow examples in these chapters as a guide to one common indenting practice. All code should be commented to improve readability. In LISP, anything on a line following a semi-colon is treated as a comment and is ignored by the interpreter.
Opinions vary on the best use of comments.
Too many comments can make code as hard to read as too few. Choosing mnemonic names for functions and variables can cut down on the number of comments needed for readability. You might wonder why you need comments if you are to be the only person to read your own code. You are not recommended to go any further in this chapter until you know how to use a program editor on your computer.