There are many shells available for Linux, but we only include the top five Linux shells in this article and thoroughly discuss their features.
Linux offers some of the best open-source shells for power users who always want to add new tool kits to their arsenal. The different types of shells in Linux offer various capabilities, but they’re basically implementing ideas developed decades ago at their core.
What is the Linux Shell
In Linux, the shell is the command interpreter in an operating system that executes other programs. It gives computer users access to the Linux system, allowing them to run various commands or functions with specific input data.
In other words, the shell is a program that takes commands from the keyboard and gives them to the operating system to perform. It accepts commands in plain text format and calls operating system services to do something.
But the shell is much more than just a command interpreter. It is also a complete programming language with constructs such as variables, loops, conditional execution, functions, and many more.
Every shell comes with its syntax and scripting features. So, let’s look at the top five most-used open-source shells on Linux.
1. Bash Shell
Brian Fox developed the Bash in 1988 for the GNU Project as a free version of the Bourne shell. Bash is similar to the original but has added features such as command-line editing.
Because Bash is the standard GNU shell, it became the standard shell on all Linux distributions. Nowadays, most modern Linux distributions provide a Bash shell by default. This open-source Linux shell is well-known in the community for its robust feature set and usability. The name is an acronym for the “Bourne-Again SHell.”
One reason Bash is considered so powerful is that it’s scriptable. A shell script is a segregation of the list of commands to optimize any task and is cost-effective, similar to other programming languages with well-defined standards.
So, anything you can type into Bash manually, you can also list in a plain-text file and have Bash run it for you.
Learning Bash can be super helpful in performing automation. It is super powerful and has lots of features such as:
- Directory manipulation
- Job control
- Brace expansion
- Tilde expansion
- Aliases
- Command history
- Command-line editing
- Key bindings
- Integrated programming features
- Control structures
- Dynamic loading of built-ins
Linus Torvalds, the creator of the Linux kernel, has said that the first two programs that he ran on his new kernel in 1991 were Bash and GCC, GNU’s compiler.
2. Zsh Shell
Zsh (short of Z shell) is an extended version of the Bourne Shell with plenty of new features and support for plugins and themes. It is a highly customizable Linux shell that packs powerful features such as tab completion, clever history, remote file expansion, and much more.
Zsh is a shell designed for interactive use, although it is also a powerful scripting language. Many of the valuable features of Bash, Ksh, and Tcsh have been merged into Zsh and its extensions.
Paul Fastad developed Zsh in 1990, and the name Zsh comes from Yale professor Zong Shao. It has become one of the most popular shells for the Linux operating system.
Some of the more essential Zsh functions are:
- Command auto-complete
- Improved variable handling
- Spelling correction
- Shared command history
- Kill tab completion
- Environment variable easy setup
- Customization
When you’re using Linux, most of the user time you spend in a terminal. If you’d like to customize your terminal and make it look professional, you can use Oh My Zsh to achieve this goal. It is a community-driven open-source framework that you can use for managing the Zsh configuration.
There are also other frameworks for the Zsh, such as Prezto, Zgen, Antigen, etc. Currently, Oh My Zsh can support 150 themes and 275 plugins.
Zsh and Bash share a similar and impressive array of features and have different tools. If you’re looking for extensibility, greater customization, and advanced features not found in Bash, the Zsh shell is an excellent choice.
In addition, Zsh is the default login shell and interactive shell in macOS Catalina, replacing Bash.
3. Fish
Fish shell is a modern command-line interface with auto-suggestions, tab completion, and syntax highlighting. It is an innovative and user-friendly command-line shell for Linux and macOS.
This shell gives users powerful features and control without compromising speed and efficiency. It is designed to be ready to use immediately, without requiring extensive configuration.
Fish inline auto-suggestions based on history work out of the box. Using your history, Fish suggests the next possibilities of completing the commands.
This shell is more colorful than the classic Bash shell. You’ll quickly notice that Fish performs syntax highlighting as you type. These colors, and many more, can be changed by running fish_config. That will open a web-based GUI where you can select a color theme and configure the look of the shell.
Another remarkable feature is the availability of the command. For example, if you type /usr/bin/linuxiac, it will show the line in red, indicating that it’s not a valid command, but if you type /usr/bin/ping, it will look normal.
Fish Shell Features:
- Inline auto-suggestions based on history
- Superb tab completion
- Syntax highlighting
- Intuitive wildcard support
- Web-based configuration
- Sane scripting
Fish is so powerful and helpful Linux shell for users who work with other shells like Zsh, Bash, and if they want to try a new and advantageous shell.
4. Ksh Shell
Ksh (short of Korn shell) was invented by David Korn of AT&T Bell Laboratories and began its public life in 1986. It is a reimplementation of the Bourne shell.
The Ksh shell’s command editor interface enables the quick, effortless correction of typing errors, plus easy recall and reuse of command history. It doesn’t provide command completion but does provide filename completion. In addition, Ksh allows the developers to create new shell commands when needed.
The Ksh shell’s command-line editing modes are the features that tend to attract people to it at first. This is because, with command-line editing, it’s much easier to go back and fix mistakes. The other prominent Ksh feature intended chiefly for interactive users is job control.
Some of the more important Ksh functions are:
- Job control
- Aliases
- Functions
- Command history
- Command-line editing
- Integrated programming features
- Control structures
- Debugging primitives
- Regular expressions
- Advanced I/O features
The Ksh shell has released different versions like pdksh, mksh, ksh88, and the most recent ksh93.
5. Tcsh Shell
The C and C++ programming languages were quite popular during the initial Linux days, and large portions of Linux were written in them. And to no surprise to no one, a new shell popped up, the C Shell that uses the vanilla C syntax model.
Tcsh is an enhanced but completely compatible version of the Berkeley UNIX Csh (C Shell). It is a command language interpreter usable both as an interactive login shell and a shell script command processor. The Tcsh can be thought as the next generation C shell.
Tcsh was developed by Ken Greer beginning in 1979 at Carnegie Mellon University. The “t” in Tcsh comes from the “T” in TENEX, an operating system developed in 1969 by BBN for the PDP-10 mainframe computer family.
Early versions of macOS X shipped with Tcsh as the default shell, but new versions became Bash. Nowadays, Tcsh is the default root shell of FreeBSD.
Tcsh’s key features are programmable command completion and command-line editing. It strikes an outstanding balance between stark simplicity and essential features.
For example, all the documentation needed to use Tcsh is located in man tcsh instead of being spread on various helper programs.
Conclusion
One of the fundamental features that helped Linux distributions secure their current stature is the Linux shell. Mastering the Linux shells gives you an alternative way of interacting with your operating system.
We encourage our readers to try on some of these shells based on their requirements and gain first-hand experience for themselves.
I hope you enjoyed the list and ranking. Please feel free to use the comment box below if you have anything new to suggest.
rich choice of shells on linux