A shell is a user program that allows the user to specify operations in a certain sequence.
As we discussed in last post about what is shell in UNIX. Now we will discuss about all different type of shell available in UNIX.
If all shell available on your system then you can switch between different shells. Following are different types of shells –
Bourne Shell (sh) – Bourne Shell is the original unix shell developed at AT&T by Stephen Bourne. Bourne shell also named as (sh) programming name. It used the symbol $. Bourne shell’s family is bourne, korn shells, bash and zsh .
korn shell (ksh) – korn shell is the unix shell developed by David korn of Bell labs. Is is considered as the family member of Bourne shell as it uses the $ symbol of Bourne shell. It is also names as ksh programmatic ally and it most widely used shell.
Bourne Again Shell (bash) – It is the free version of Bourne shell and comes with all UNIX/Linux systems as free with some additional features like command line editing. Its program name is bash. It can read commands from file called scripts.
Like all Unix shells it supports the following:
- File name wildcarding
- Hear documents
- Command execution
- Variables and control structures for condition testing and iteration
C Shell (sh) – C shell is the UNIX shell created by Bill joy at California university as an alternative to Bourne shell – Unix original shell. C shell along with Bourne and Korn, are there most popular and commonly used shells. csh is the program name for C shell.
Tab C chell (tcsh) – It is the family member of C shell with additional features like enhanced history substitution to reuse commands, spelling correction and word completion.
Please correct me, if anything found wrong here. Please comment also for any additional shell type in UNIX.