BASH or Bourne Again Shell is an interface(program) between the user and the Operating System. BASH is just an application just like others, but not an ordinary one. It is quite powerful when used to its potential. It is used in various aspects of computing. No, it's not only for server admins, but it specializes in that field though. We'll see how we can use Bash to perform several tasks quite powerfully. Not just automation, you'll be surprised what Bash is capable of.
BASH is just like any other shell such as z-shell, c-shell, Korn shell, and Bourne shell. BASH is a variant or update version of the BOURNE shell. Technically it has quite advanced features than the Bourne shell, such as arithmetic operators, signal handling, command-line completion, and tons of quality of life improvements. So what can Bash do? Well pretty much anything, it is close enough to call itself a programming language but not quite enough. You can call it the programming language of the command line.
Bash also has built-in features such as variables, loops, if-else conditional statements, functions, and all but there are no concrete data structures to work with. Some of them quite useful structures are built-in such as arrays and dictionaries. It can perform arithmetic, logical and programmatical operations inside of a terminal or command line. It can make use of some other programs such as grep, awk, sed, cURL, find, wc, the list is quite large. Most of the commands are quite versatile and can be integrated with each other quite well. Certain concepts such as command piping, brace expansion, and others provide a great integration and feasibility to make quite a lot of applications using Bash. Certain commands such as grep, cURL, sed, cat, touch are quite incredible and are used a lot in day-to-day use cases. Let's take a quick look at how actually we can use Bash to perform a basic task.
Append to file from terminal
From the above image, I edited a file without leaving the terminal. That can be lame but powerful in certain conditions. Anyways, that was just an example, but you can see where it can go. It can be extremely powerful for some repetitive tasks in programming or any other tasks. it can be also quite vividly used in the upcoming fields.
Well, Bash has some epic applications, some of them might surprise you but they are indeed liable to call themselves features of Bash. Let's dive in then.
This is the most known feature of Bash as it stands upright on top of other tools and programs. Bash is most commonly used by system admins to automate repetitive tasks in managing a system. These tasks may include backing up files, managing file structures, monitoring the performance of a system, and debugging any errors and issues in the system on a regular basis to ensure the smooth functioning of a system. So, it makes quite a lot of sense to automate certain tasks that might waste time and effort to do them over and over again. Hence, Bash is the system admin's best friend and also for programmers to automate certain tasks and compilation of programs.
This is another aspect where Bash just makes things flawless, just flawless. It's much more easy, straight forward and intuitive to manage or handle files in Linux/ Unix operating systems. The tools and command-line utilities such as grep, awk, sed for matching patterns using regular expressions, cat, tac, touch to create and make changes to the file. There are a plethora of ways to make files and directories using Bash utility tools. We can also make a bunch of files at once, make the structure of a file system at once just using Bash and its commands.
This is a concept which many people use but are unaware of. People using Linux for programming are mostly using bash as their environment to make, compile, run files of the program. That is quite a powerful environment to work with as it is quite customizable and efficient as compared to Windows at least. Even macOS used Bash till a certain time but migrated to zsh for silly reasons about security issues on Bash. But still, Bash is the tool that most programmers use while interacting with the web servers or any other programs that deal with some kind of interface to the operating system especially Linux/ Unix. So, it is worth noting that Bash is the default development environment for many programmers.
Networking is another aspect where Bash also some quite remarkable tools to play around with. Bash has certain powerful tools like Nmap, aircrack-ng, ping, and many other networking tools which makes it quite a good choice for ethical hacking and network security as well. This domain is quite complex in terms of concepts as it makes the core IT domain. Bash also provides ways to manage the network using some well-equipped tools and programs to make it quite user-friendly.
Yes, This is possible by making use of certain tools such as cURL to extract the content from the web and then using grep, sed, awk, or any other pattern/ regex matching tools to filter out the content. This might be very useful and informative for beginners trying to understand how web scraping actually works. Web-scraping can be learned this way so as to understand "Under the Hood" working of some utility and frameworks for web-scraping. This is some super great stuff for a simple shell to do in a standalone way though it may require a good skill of regexes and how the web works to make full utilization of the powers of Bash.
OK, now I just know about these many applications about Bash but if you know any other please let me know in the comments. Bash is a great tool and I don't why it's not quite famous but still used a lot. Maybe I am wrong here, just an opinion though. So, I hope you might have got some insights to dig deeper into Bash and learn to improve efficiency and skills.
So, that's it from Bash and its application in a high-level view, there is a huge field and community for Bash, just because of some threats Bash is not going anywhere, still, zsh is getting replaced in most cases, but the concept and tools remain the same. At the end of the day, its the skill rather than the version of any tool that matters Happy Coding and have a blast learning Bash :)