Pointer (computer programming) facts for kids

A pointer in computer science is like a special kind of variable that doesn't hold a regular value, but instead holds the exact spot (or "address") of something else in the computer's memory. Imagine you have a treasure map, and the "X" on the map isn't the treasure itself, but it tells you exactly where the treasure is buried. A pointer is like that "X" – it points to where the real data is stored.

Pointers are very small, so they don't take up much memory (RAM). Copying a pointer is much faster than copying a huge piece of data because you only need to copy the tiny address, not the whole big item. When a programmer wants to get the actual data that a pointer is pointing to, they "dereference" it. This is like following the map to dig up the treasure!

How Pointers Are Used

Pointers are super useful for organizing information in clever ways. One common use is in something called a linked list.

Linked Lists Explained

Imagine you have a list of your favorite books, but instead of writing them all down on one piece of paper, each book is on its own small card. To keep them in order, each card has a little note saying, "The next book in the list is on card number 5," or "The next book is on card number 12."

In a computer, these "cards" are called records or "nodes." Each record holds some information (like a book title) and also a pointer. This pointer tells the computer where to find the next record in the list.

Chaining Records Together

These pointers act like a chain, linking all the records together. Because each record points to the next one, the computer can easily go from the first record to the second, then to the third, and so on, even if the records are scattered in different parts of the computer's memory.

Sorting with Pointers

One cool thing about linked lists is that you can easily change the order of the records just by changing the pointers. If you want to put a new book in the middle of your list, you don't have to rewrite the whole list. You just change a couple of pointers to make the new book fit in the right spot. This makes linked lists very flexible for adding, removing, or sorting data without moving large amounts of information around.

See also

• In Spanish: Puntero (informática) para niños