The object-oriented way of programming arose out of a need to build better, large software systems.

In the object-oriented programming style, the program describes of a bunch of objects and their features and operations.

When objects are able to execute, they are said to be instantiated.

Each object has its own features called its state , and its own operations called its methods .

The programmer writes statements which send messages to the various objects.

When an object receives a message, it invokes its own procedures - its methods to perform the action.

Let's see how this is done in RoBOTL, a language which introduces object-oriented concepts using a C++- like syntax.

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