Software libraries play a crucial role in programming by providing pre-written code that developers can reuse to perform common tasks. This enhances efficiency and encourages best practices, allowing programmers to avoid the redundancy of writing code from scratch. Libraries often contain functions or APIs for specific functionalities, such as data manipulation or graphics rendering. By leveraging these resources, developers can focus on building the unique components of their applications, speeding up the development process and improving code quality, making them an essential tool in modern software development.