Been learning the UNIX Shell, which uses a command-line interface (from a terminal) .. something I've wanted to do ever since we upgraded to the Virtual Private Server last year. (Linux is a variant of UNIX.)
Even basic knowledge of (how to use) the Linux command line makes life administering a VPS much easier.
The Shell is simply a program that allows users (like me) to interact with the operating system (sometimes termed the 'kernel'). It can be conceived of as a 'layer' sitting between you and the operating system .. hence the term » shell.
Several shells exist, but nearly all Linux distributions come with » bash (Bourne Again Shell) .. cuz it's free, powerful and easy to use.
On my laptop I have installed a copy of Ubuntu Linux that I use to learn the shell (practice). Before jumping into learning the Shell, I figured this was a good time to upgrade my 'installation' of Ubuntu .. to the latest release (» v9.04, 'Jaunty Jackalope').
So I downloaded » this virtual machine (1.1 gig, using uTorrent). Had trouble getting it connected to the Internet, but that was due to my own inexperience with VMware, and not due to any short-comings of Ubuntu.
Anyway, I am really digging learning the Shell, cuz it's something I can use right away. For example, yesterday I upgraded the blogging software we use here at Radified (Movable Type) to the latest version (» 4.26). Something that used to take hours to accomplish was done in minutes .. (using a series of Shell commands). Beautiful.
