CLI Explained in a Straightforward Way
Cloud computing services like Amazon AWS are making it easier and easier for businesses and developers to access an ever-increasing number of networks, devices and systems. However, managing so many different domains can be quite a hassle. The best tool for this has proven to be a method that has actually been in use since the invention of the computer: CLI.
CLI instead of the mouse
CLI stands for Command Line Interface (CLI). In German, the CLI is often referred to as the command line or command line. It is a user interface that accepts text-based commands from a user. CLI is therefore used for applying, displaying and managing computer programs.
The command line is often represented as a black box with white text blocks. Here the user either enters a command independently or responds to a prompt with a command. The system managed by the CLI responds with a message, table or list. The content of this message provides information about whether and how a system or program is executed.
In simplified terms, you can imagine the use of the CLI like this: Instead of using a mouse to communicate on a graphical user interface such as Microsoft Word, the user enters commands to run or manage a system into the CLI in the form of a message. In fact, this is exactly how computer systems were operated before the mouse was invented and implemented in computer systems.
The shell
The CLI or command line is also run by a piece of software called a shell or command line interpreter. The best known shells are certainly the PowerShell for Windows and the Bash for Linux and macOS. The shell can be thought of as the proverbial shell of one or more computer systems. Directly underneath is the core of the various operating systems.
Since the shell is the immediate layer before the operating system, it can be used to perform actions that cannot be performed by any other type of interface. For example, moving data, deleting locked data, or even automating system executions. And this is exactly why the CLI or the shell is so important for modern system management.
Because with the CLI also innumerable different systems can be managed effectively. Commands can be automated, simple debugging can be performed, and even complicated command lines can be saved for repeated use. The CLI thus effectively provides an interface with options for accessing and optimizing entire systems.
CLI vs GUI
As users of a PC in everyday life, almost all of us now use a graphical user interface (GUI). For example, when using Windows, Linux or Apple. Theoretically, many tasks of a CLI can also be performed by such a GUI, which of course can be operated by mouse and thanks to the graphical user interface is much easier to use.
As a system administrator, however, you quickly reach your own limits. Firstly, a GUI cannot be used to automate system execution commands. Secondly, managing countless systems with a GUI is a real administration nightmare. In addition to this, a CLI can be used for partial troubleshooting, and this can be done without much administrative effort.
The big disadvantage of CLIs, however, is the increased complexity of the applications. In order to be able to use a CLI really smoothly and quickly, the complicated syntax commands must first be learned by heart - and these can differ from shell to shell. This, of course, makes it take much longer for new administrators and moderators to learn the ropes.
Advantages and disadvantages of CLI
The CLI is thus an incredibly powerful tool for effectively managing even complicated systems. Moreover, it can be used to execute much more detailed and complicated commands than a GUI. However, this also comes with a disadvantage. Below, we have summarized the most important advantages and disadvantages once again for a better overview.
Advantages:
- the management of multiple systems becomes much more effective and easier
- scripts can be automated for simplified use
- command lines can be used for troubleshooting
- more detailed and complex commands can be given through CLO, which in turn allows for much smaller-scale control of programs and systems
Disadvantages:
- high complexity requires a great deal of effort to learn
- different Shells can use different commands, which complicates the application further
- for a smooth use first the complicated syntax structures must be learned
The application areas of a CLI
Even though the basic idea of the CLI is virtually as old as computers themselves, the CLI is now being used in more and more areas. So among other things:
- Operating systems
- application programs
- computer games
In addition, CLI is becoming increasingly important for cloud computing. This is because the great advantage of cloud computing, that it can be used to create incredibly complex systems that can access all enterprise information at any time, can also quickly become an administrative burden.
That's why Amazon uses the AWS command line interface (CLI) for its cloud service, for example. This allows a user to manage all aspects of all AWS services used with a single tool. Use cases like this illustrate that CLI will play an increasingly important role in cloud computing in the future.