There is more to the shell, the terminal’s interpreter software, than commands composed of alphanumeric characters. In addition to those familiar programs, there is a whole host of processing tools hiding behind the symbols of a standard keyboard.
To say nothing of their incredible potency in combination, each one is so powerful on its own that it helps to take a methodical approach to get familiar with them. With that in mind, I’ll narrow the focus here to two of the more practical symbols: the pipe (“|”) and the wildcard (“*”).