Macro deserve their own file for compiling them.

Macros exploit the fact that lisp forms are just expressions meant to be evaluated.

Lisp forms can be constructed with the same primitives that generally manipulate lisp expressions.

The only difference between the appearance of macro and ordinary definition is that one uses defmacro and other uses defun.

Macros do not evaluate their arguments.

Defmacro can be used to define procedure called macro procedure.

Macro use their arguments to build intermediate forms and it evaluate the intermediate form to produce a value.