Class representation in memory

Question

Could someone explain the following expression :
A class is represented logically until an instance of it is created . So is gonna be represented since everything should be in the memory !!

Answer 1

Every computer programm which is executed, generates a process in memory. A process particularly consists of the instruction pointer, the process register, the code segment, the data segment, the stack segment and the heap.
When creating objects of a class, memory of the stack and/or heap is allocated for each instantiation.
But no memory of the stack or heap is used for the definition of a class.
When we talk about memory allocation, we say “memory”, but mean stack and/or heap.