If you’ve spent any time in a Linux or Ubuntu terminal, you’ve already met mkdir. It’s usually one of the first commands people learn, right after ls and cd. Most tutorials stop at “mkdir folder_name” and move on — but mkdir can do a lot more.
In this article, I want to go deeper and show you how to use mkdir like a pro. This is a practical, hands-on guide, written from daily Linux usage, not just theory. We’ll start with the basics and then move into advanced usage, including permissions, modes, regex-style expansions, and building entire directory trees with a single command.