Shell
Shell is a type of computer program that allows Linux and Unix operating system users to control their command line interfaces.
Shell allows users to establish efficient and direct communication with operating systems. This makes it extremely important and popular.
Shell is sometimes confused with operating systems. However, Shell is not an operating system. It's a way of creating an interface with the operating system and running commands.
Having programming knowledge is not a prerequisite to learn Shell. Since Shell uses some natural language commands, even those who don't know programming can easily learn Shell. However, to create more complex applications in Shell, more practice is necessary.
In Shell, each command script is considered a separate language. Command scripts are one of the simplest ways to create automation. These command scripts provide control structures for data scientists and DevOps specialists.
What Does Shell Do?
In short, Shell does the following:
- Get a list of files or directories
- Check the time and date
- Create and copy a file
- Delete file
- Sorting files
- Create user accounts
- Manage users according to the security policy
- Find out available and empty memory
- Get information about local or remote servers
- Provide automation
and much more complex tasks.
History of Shell
The Shell script was created in the early 1960s by MIT computer staff Louis Pouzin. That's where it got its name.
Who Uses Shell?
Nearly everyone who uses a computer can use Shell. However, especially system administrators, DevOps specialists, data scientists and programmers use Shell.
Shell is used to automate tasks and applications and backup data.
Why Is Shell So Popular?
Shell can be used on almost every operating system. It's efficient and easily updatable. The Shell performs necessary and routine backups by monitoring the computer's operating system. This is what makes it so popular and preferred by data scientists.
There's no need to change the Syntax in Shell because the Syntaxes of Shell are the same as the ones entered in the command line.
Shell Commands
Shell has two categories: command line shell and graphic shell. Command line shells are the category where users receive input commands and use command line interfaces to display the output.
A graphic shell is a category where graphic user interfaces (GUI) are used for basic operations such as opening, closing, and saving files.
Writing command scripts is easy and fast. Debugging from these command scripts is also quite straightforward. Examples of Shell (shell) commands are as follows:
- pwd: To find out which directory you are in, the “pwd” Shell command is used.
- man command: To find a command in the guide, the “man command” Shell command is used.
- less/more file 1: For editing the text file, “less or more file 1” Shell command is used.
Why Is A Command Script Created In Shell?
- Creating a command script in Shell allows users to automate their tasks. Thus, repetitive tasks become automated. Script files containing commands can execute themselves as commands.
- For performing their tasks, users can create their own customized environments by generating a Shell command script.
- Creating a Shell command script allows for prototyping.
- Shell minimizes errors in tasks.
How to Access Shell?
In Mac or Linux operating systems, Shell is accessed through a program named “Terminal”. Terminal is already installed in Mac and Linux operating systems.
The Terminal is a window or area where commands are written. In Windows operating systems, a separate program needs to be downloaded to access Shell.
Does Shell Have Any Importance For A Career?
Although Shell doesn’t have a direct importance in a career journey, being a learned skill provides some advantages for programmers and data scientists. A data scientist who knows how to create a command script in Shell automates their tasks and completes them quickly. This shows that Shell is a necessary skill to learn. Additionally, Shell scripts help in making languages more efficient.
