Most objects have more than one possible read syntax. In Lisp, an expression is primarily a Lisp object and only secondarily the text that is the object's read syntax. Often there is no need to emphasize this distinction, but you must keep it in the back of your mind, or you will occasionally be very confused.
Every type has a printed representation.
Some types have no read syntax, since it may not make sense to enter objects of these types directly in a Lisp program. For example, the buffer type does not have a read syntax. However, evaluation and reading are separate activities. See Input Functions , for a description of read , the basic function for reading objects.