If you feel daunted by using the command line, don't!
It's really not that difficult as long as you understand the basic paradigm and you know a few of the commands. It's always good to learn more, of course, but you can get by with a surprisingly simple set of commands.
Everything in a computer is a program
The command line is a program - it's a type of program known as a shell and you probably have the bash shell.
This means that it's a unix shell / terminal / command line.
In Unix, everything is a program. A shell is a program for running other programs.
When you type ls (and press enter), you are running a little program that knows how to list all the files in the current directory (a directory is a folder)
Even though the ls program isn't in the current directory, the shell manages to find it because it is in your ... path.
The history is very useful. You can pull up previously entered commands.