Also, you have to know about the infamous Deppen Leerzeichen 😀
Normally in UNIX ‘special’ characters are handled with a preceding (backslash) character. this is the escape character, and the character after this is not treated ‘special’.
In UNIX in most shells the ‘ character includes a command that is executed by the shell, and its output is being inserted in the current expression.
most famous is prolly something like:
apt-get install gcc_'uname'*