object-oriented programming

Computer programming based on objects, in which each object has its own program code and data and can interact with other objects. Data items are closely linked to the procedures that operate on them. For example, a circle on the screen might be an object: it has data, such as a centre point and a radius, as well as procedures for moving it, erasing it, changing its size, and so on.

The technique originated with the Simula and Smalltalk languages in the 1960s and early 1970s, but it has now been incorporated into many general-purpose programming languages, including Java, C++, and Eiffel.