Extensible programming means writing computer programs that can be changed or extended easily. This means that when you write a program it can be changed or adjusted with minimal effort. For example, if you write a program to make a calculator, it can be easily adapted to allow the user to type in their own numbers, or to calculate different kinds of math problems. It also means that you can use other people’s programs and add your own features. For example, you can take someone else’s program for a calculator and add buttons to allow the user to type in extra numbers or calculate different kinds of problems. That would be an example of extensible programming.