In this chapter, you learned about the working-directory concept and tools dealing with it. You also explored functions to inspect the working environment, modify global options, and manage the library of packages. Now, you have the basic knowledge to manage your workspace.

In this next chapter, you will learn several basic expressions, including assignment, condition, and loop. These expressions are the building blocks of program logic. I will show you how to write efficient and robust control-flow expressions in the next chapter.