The main purpose of software development frameworks is to provide developers with pre-built tools, libraries, and best practices that streamline the software development process. By utilizing frameworks, developers can focus on building unique features without starting from scratch, which enhances productivity and reduces the likelihood of errors. Frameworks promote code reusability, consistency, and standardized practices, making it easier for teams to collaborate effectively. They often include built-in functionalities for tasks like routing, database interactions, and user authentication. Popular frameworks, such as Angular, React, and Django, are widely used across various programming languages.