What in the world are you talking about? The whole point of this tutorial is to teach command-line basics as a first step toward becoming a software developer. From the tutorial:

Many programming tutorials either gloss over the command line or assume you already know it. But understanding the basics of the command line is absolutely essential to becoming a skilled developer. Indeed, if you look at the desktop of an experienced computer programmer, even on a system with a polished graphical user interface like Macintosh OS X, you are likely to find a large number of “terminal windows”, each containing a series of commands at a command line (Figure 1). Proficiency at the command line is also useful for anyone who needs to work with developers, such as product managers, project managers, and designers. Making this valuable skill accessible to as broad an audience as possible is the goal of Learn Enough™ Command Line to Be Dangerous.