Separation of concerns

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.

Description

A concern is a set of information that affects the code of a computer program. A concern can be as general as the details of the hardware the code is being optimized for, or as specific as the name of a class to instantiate.

Modularity

A program that embodies SoC well is called a modular program.

Modularity, and hence separation of concerns, is achieved by encapsulating information inside a section of code that has a well-defined interface.

Encapsulaton

Encapsulation is a means of information hiding.

Layering

Layered designs in information systems are another embodiment of separation of concerns (e.g., presentation layer, business logic layer, data access layer, persistence layer).

Value

The value of separation of concerns is simplifying development and maintenance of computer programs.

When concerns are well-separated, individual sections can be reused, as well as developed and updated independently.

Of special value is the ability to later improve or modify one section of code without having to know the details of other sections, and without having to make corresponding changes to those sections.

See also

• Abstraction principle (programming)
• Aspect-oriented software development
• Cascading Style Sheets
• Concern (computer science)
• Core concern
• Coupling (computer programming)
• Cross-cutting concern
• Holism
• HTML
• Modular design
• Modular programming
• Orthogonality#Computer science
• Semantic HTML
• Separation of presentation and content
• Separation principle -
• Single responsibility principle
• Style sheet (web design)
• Web page layout

External links

• Separation of concerns @ Wikipedia