Computer Science - Artificial Intelligence - Discussion

In the Jargon, car is "non-destructive'. This feature turns out to be important. The CDR of a list is the rest of the list, that is, the cdr function returns the part of the list that follows the first item. If it were not, the Lisp interpreter would try to evaluate the list by calling rose as a function.

But car is an object. How an object relate to function return value? Please anyone explain in detail.

It is a system in-built function in lisp library.

It returns the first element of a string or a digit.

Why is the answer car? Please describe it.