[flavio81]

> Sorry if dumb question but how is this possible when it's garbage collected?

On a big or complex system you end up at least doing one or both or two things:

a. Having to manage many temporal (transient) objects in memory. Thus you end up doing some sort of garbage collector, either doing it yourself, or using the facilities provided by the languages, or a library.

b. Allocating fixed big blocks of memory (such as arrays, or doing a "malloc") and then using this block of memory as your storage area, which then you manage.

Usually on C programming you do (b), although you can also do (a), it is not so easy.

Usually on Common Lisp programming you do (a) very easily, but you can also do (b) by allocating an array and a bit more stuff. It is not difficult, really.