Object-oriented programming allows procedures about objects to be created whose exact type is not known until runtime. For example, a screen cursor may change its shape from an arrow to a line ...

viewing and totalling are examples of its behavior. Objects (individual invoices) inherit this behavior and combine it with their own data elements. See CRC cards and object-oriented programming.

An abstract class is a template definition of methods and variables ... For example, using the keyword implements will make a Java interface, while the keyword extends makes an abstract class.

Most object-oriented programming languages don't allow variable, method, class and function names to ... where there is no white space between compound words. Here's an example of snake case, ...