It sneaks up on you. Before you know it, you're typing commands into the little interactive "Command Prompt" window called "Terminal" or "Konsole" or variously named weirdly in other flavors of the system. And as you do, you get packages of downloads, and fresh little programs, and you learn about things like "superusers" and you begin to pick up on the protocol for the language conventions used in probing the "inner sanctum" for more software or help with that which you have. It sneaks up on you. And suddenly, you're in the thick of it.
Windows doesn't help you modify the components of the system to suit yourself, and maybe that's why I'm attracted to Linux. It's configurable. And it works!