Very Basic bash

If you are logged into a terminal window on a Unix/Linux/OS X machine, you are interacting with an application called a "shell" (called this because it serves as the outer shell of the operating system). There are several shell programs out there, including sh, csh, tcsh, and bash. You can find out which one is running by typing echo $0 at the terminal prompt.

bash is perhaps the most common shell these days. It has most of the features of other shells. In particular, you can use the up arrow to see previous commands and use the left arrow and back space keys to edit them. Another nice feature is file name completion; if you type a tab after typing just enough of a file name to uniquely identify it, the shell will complete the file name for you. If you have not uniquely identified it, it will complete as much as it can and then you can hit the tab key again to see a list of the files that match the substring you have typed in. You can look at the bash manual page for many more details about if you are interested.

If you are new to UNIX, you may want to look at the basicUNIX document. One of the most useful commands listed there is the exit command, which you can use to log out.

If you are interested in learning vi, you may want to look at the basicVI document.