What is "back-end" development?

Back-end development refers to the server-side of a web application, which manages and processes requests from the client side, interacts with the database, and contains the core logic of the application. It is responsible for executing operations such as data storage, retrieval, and processing, ensuring that the necessary information is delivered to the front-end where users can interact with it.

Back-end development typically involves languages and frameworks such as Python, Ruby, Java, PHP, and Node.js, alongside database management systems like MySQL, MongoDB, or PostgreSQL. This area of development is crucial because it ensures that the application runs smoothly behind the scenes, handling business logic and database transactions, while the front-end focuses on user interfaces and experience.

In contrast, the other choices emphasize aspects of web development that are related to visual elements, user interactions, and layout design, which are all considered part of front-end development rather than back-end development. Thus, option C accurately captures the role and responsibilities of back-end development within the broader web development landscape.