What is a pointer exactly?
Throughout an introduction to computer science class, you may hear references made to wonderful things called pointers, but until you experience them for yourself, you're missing out on a wonderful world of possibilities. Pointers are a necessary facet of almost every computer program written, whether for personal, academic, or commercial use. This tutorial will explain when and how to use them.
What exactly is a pointer? Stated simply, a pointer is nothing more than a variable that holds an address in the computer's memory. This is where a pointer gets its name. A pointer variable holds the address of a certain piece of memory in the computer; in other words, a pointer points at a specific location in memory. In essence a pointer is nothing more than a variable that holds a number that is the address of a specific memory location.
Pointers and Memory
For now, let's think of memory as a big blob of storage space where we can put information that we later want to retrieve (this isn't far from the truth).
Let's say we have a simple program as follows:
What happens when we run this program? First, the computer sets aside a little bit of memory to hold the integer steve.
It then stores the value 220 into that variable.