TOP 9 Linux Shells

Various Linux distros come with various default shells, but users can install any specific one on their operating system if necessary.

If you want to change your default shell, then you should review our article because we will provide a full guide of the most popular shells, so you will have a broader overview of all the possible variants.

The importance of the Linux Shell

Shell is a command-line interpreter that is necessary for passing commands to the OS. This tool represents the OS’s interactive interface and the utmost layer of the kernel. With its help, programs and users can send signals and open low-level utilities.

Terminal helps to interact with the utilities. If any command runs in the terminal, the shell is responsible for the search, evaluation, and execution if it is found.

1. Bourne Shell

Bourne shell is considered to be an initial Unix shell that was launched in 1979. It is called sh, and is usually located in /bin/sh. For entering the root prompt use #, and the user prompt with $.

This shell variant quickly gained popularity because of its speed and compactness, but there are certain lacking features, such as:

• Command history.
• Arithmetic and logical expansion.
• Autocomplete and other features.

2. C Shell

C shell was launched in the late 1970s, and the major point of its creation was the improvement of the interactive usage and the mimicking of the C language. Also, its launch was aimed at the creation of stylistic consistency across the system.

The location of the shell is in /bin/csh, and with the help of #, you can enter the root user prompt, and with % - the regular user.

Here are the most common features:

• Built-in expression grammar.
• History of the previous command.
• Availability of the relative home directory.
• User-defined aliases for programs.

Among the most common drawbacks, we can specify:

• Not fully recursive.
• Syntax inconsistencies.
• No support for regular output and input file handles.

3. TENEX C Shell

TCSH is a so-called extension of the C shell that appeared at the beginning of the 1980s. This specific shell is compatible with csh, and there are some concepts and features that are taken from the TENEX OS.

To enter a root prompt, use hostname:directory#, and for the user prompt, you should use hostname:directory>. This shell is used as a default variant for FreeBSD and early Mac OS.

Here are some common features of the shell:

• Job control.
• Availability of the more advanced command history.
• Wildcard matching.
• Programmable autocomplete.

Because this shell is an extension of the C shell, there are lots of similar drawbacks, so we are not going to mention them once again.

4. KornShell

KornShell was created at the beginning of the 1980s, and it is considered to be a language based on the Bourne shell. The shell is usually located in bin/ksh, and all the prompts are activated the same as in the Bourne shell with the # and $.

This shell is oriented towards programming features and interactive commands and has some similarities with both the Bourne and C shells.

Here are several features of this shell:

• Object-oriented programming.
• Compatibility with Bourne.
• Availability of floating-point arithmetic and Maths functions.

5. Debian Almquist Shell   

Debian Almquist Shell or Dash was created later in the 1990s and is considered to be a Unix shell. This shell is a default variant on Debian and Ubuntu systems. The executable path might be in bin/sh or /bin/dash. The root and default prompts are identical to those in the Bourne.

Here are some common features:

• Needs minimal CPU, RAM, and disk space when comparing with other variants.
• Really high executable speed when comparing with bash and some other alternatives.

The only major challenge that may be connected with the shell is bash incompatibility. That means bash scripts should be reworked for proper functioning.  

6. Bourne Again Shell

Bash or Bourne Again Shell was launched in 1989, and it is considered to be a Unix shell. This variant is a default option for some early macOS and lots of Linux distros. The location of the shell is in bin/bash, and the regular user and root user prompts are the same as in Bourne.

Some of the most common features that are specifically related to the shell are:

• Availability of the command completion.
• Command history.
• Brace expansion.
• Support for Heredoc.
• Signal handling and basic debugging.

7. Z Shell

Z Shell was launched at the beginning of the 1990s as an extension of Bourne. This usable variant is located in /bin/zsh. The prompt for the root user is hostname#, and for the regular user user@hostname location %. This shell is a default option for Mac OS and Kali Linux.

Here are some features of the shell:

• Available extensibility via the plugins.
• Shared history among all running sessions.
• Different compatibility modes.
• Autofill of the command name and correction of spelling.

8. Friendly Interactive Shell

Fish or Friendly Interactive Shell was launched in the middle of 2000s, and it is considered to be the most user-friendly variant with the diversity of features. It is usually located in /usr/bin/fish, the root prompt is root@hostname location#, and the user prompt is user@hostname location>.

Here are some common features of the shell:

• Availability of the command history with the search options.
• Advanced tab completion depending on the current history of the directory.
• Descriptive error messages.

9. Elvish

Elvish was created in the middle of 2010s with the intention of having more consistency and clarity. Usually, the shell is located in /usr/bin/elvish.

Here are the most common features of the shell:

• Awesome interactive editor with history navigation and syntax highlight.
• Smart tab completion.
• Structured data support.

Summing up

Now, after reviewing our top Linux shells, you have a general understanding of the most popular options and their basic features. There are plenty of other shells for specific use cases, and every one deals with various troubles.