OOPs, concepts, OPs, SoD concepts and a separation of concerns

What are the four main oops concepts?

OOPs, concepts in Java are the main ideas behind Java's Object Oriented Programming. They are an abstraction, encapsulation, inheritance, and polymorphism.

What is separation of duties?

Separation of duties (SoD) (also known as "Segregation of duties") is the concept of having more than one person required to complete a task. In business the separation by sharing of more than one individual in one single task is an internal control intended to prevent fraud and error. The Law of Demeter (LoD) or principle of least knowledge is a design guideline for developing software, particularly object-oriented programs. In its general form, the LoD is a specific case of loose coupling.

In computer science, separation of concerns (SoC) is a design principle for separating a computer program into distinct sections, such that each section addresses a separate concern. A concern is a set of information that affects the code of a computer program.

Technocracy is a system of governance where decision-makers are selected on the basis of their expertise in their areas of responsibility, particularly scientific knowledge.