What is the concept of "Separation of Concerns" in software design?

Separation of Concerns is a foundational principle in software design that advocates for organizing a program into distinct sections, each handling specific concerns or functionalities. By dividing the software into separate modules or components, developers can focus on one aspect of the program at a time, which simplifies reasoning about the code, enhances maintainability, and facilitates collaboration among team members.

When using this principle, changes in one part of the system are less likely to affect other areas, reducing the likelihood of unintended consequences and bugs. This modularity allows for easier updates, testing, and scalability, as each component can be developed, tested, and maintained independently. It encourages a clearer structure and a more organized approach to software development, leading to improved overall quality and efficiency in the codebase.

This principle contrasts sharply with the idea of merging different functionalities into one module, which can lead to tightly coupled code that is harder to understand and maintain. Additionally, it promotes a clearer distinction between different aspects of software development, avoiding complexities that arise from intermingling different concerns. Ultimately, applying Separation of Concerns helps make software systems more understandable and adaptable over time.