As your programs grow in complexity, managing code effectively becomes essential. This chapter introduces techniques for organizing your Julia code and managing external dependencies.

You will learn about modules, which help you group related functions and data, preventing name conflicts and improving code readability. We will then cover Julia's built-in package manager, Pkg. This tool is fundamental for incorporating external libraries into your projects, managing different versions of these libraries, and setting up reproducible project environments.

By the end of this chapter, you will be able to structure your Julia projects logically, use modules to create reusable components, and confidently manage packages to extend Julia's capabilities.