Modeling the relevant attributes and interactions of entities as classes to define an abstract representation of a system.
This involves identifying the key entities in the system and defining their properties and behaviors as classes. For example, in a banking system, classes may include "Account" with attributes such as account number, balance, and owner, and methods for depositing and withdrawing money.
Classes can also interact with each other through relationships, such as inheritance, aggregation, or association. For instance, a "Transaction" class may be associated with an "Account" class to record the transactions made on a particular account.
By modeling entities as classes, developers can create a blueprint for the system that accurately represents its structure and functionality. This allows for easier design, implementation, and maintenance of the system.