The shell is the program that acts as a user interface to send commands to the kernel. The kernel then interprets the command and tells the CPU and other computer hardware how to carry out the particular task.
Every time a user logs in, a shell is started. The type of shell is up to the user, but most often the default is set to
Bourne Again Shell shell includes the basic features common to all unix shells, including pipelining, here documents, command substitution, variables, control structures and wildcards. It is the most common default shell for user accounts.
C Shell was created by Bill Joy at the University of California, Berkeley. His main intent was to create a shell with C language-like syntax. Thus, it included things like control structures and expression grammar.
Other features included history and editing mechanisms, aliases, directory stacks, tilde notation, cdpath, job control and path hashing.
tcsh was developed to be compatible with the C shell. The t in
tcsh comes from TENEX, which was an operating system.
tcsh is very close to
csh with extensions like command-line completion, command-line editing and other features. Mac OS X's used to come with
tcsh as default, but switched to bash in Version 10.3.
Z shell was designed for interactive use.
Some of the features of z shell include spell check, editing of multi-line commands in a single buffer, improved variable and array handling, customization, programmable command-line completion and themeable prompts.
As you can see, there are plenty of shells to choose from! As you get to know more about the terminal and shell, you may want to upgrade to another shell. For now, however, bash will suit our needs just fine.
Stretch out your back and relieve your back muscles with inversion therapy. This device counteracts the forces of gravity on the body by decompressing and elongating the spine. By using this product just ten minutes a day, you can be well on your way to improved circulation and posture while relieving muscle aches, back pain and stress.$$ Check price
This book approaches system administration in a practical way and is an invaluable reference for both new administrators and experienced professionals. It details best practices for every facet of system administration, including storage management, network design and administration, email, web hosting, scripting, and much more.$ Check price