The command line is one of the most important tools for a Linux/UNIX power user. Bash is the default login shell on Linux and Mac OS, and adding it to your skillset will open up a whole new world of possibilities. For one thing, it gives you access to a huge number of command line utilities, simplifying many everyday tasks. But Bash also provides you with a powerful scripting language for automating just about anything. For remote access and system administration, Bash is an absolute must.