The evolution of command line interface (CLI): A historical insight

Highlights

You’ll learn about the history and evolution of command-line interfaces

• 1960s: Early use of computers with minimal graphical capabilities
• 1970s-80s: Development of UNIX and widespread adoption in tech
• 1990s: Adoption of the more user-friendly graphical interfaces, but CLI remains vital
• 2000s to present: Integration with containers, cloud tools, and modern operating systems

Discover how the command line interface has evolved while remaining essential for tech professionals. Create the environment for your developers with the Contentstack CLI in your composable DXP. Talk to us today to learn more.

Command-line interfaces (CLIs) allow users to send commands and perform powerful operations. With command-line shells, developers can run programs, manage computer files, and perform various tasks. Software developers who use CLIs are efficient, fast, and versatile because they can accomplish tasks with a single command.

Early beginnings of CLIs

Command-line interfaces were first used in the mid-1960s on computer terminals. Before then, people used punch cards.

Early history and evolution of CLI in computers

The command line interpreter for CTSS was one of the first CLIs, developed in 1961. The Multics shell, developed in 1965, introduced many features that are still present today, like the command history and tab completion.

Command-line interfaces (CLIs) were used before graphical user interfaces (GUIs), from the mainframe era in the 1950s to the 1960s. In the 1960s, minicomputers with multiple processors were invented. Due to their limited resources and applications, minicomputers relied on CLIs.

After microcomputers boarded, a new user base was introduced to CLIs. Innovative CLI features, such as command completion, history, and aliases, were also developed to overcome hardware limitations.

Unix command line

In the 1970s, the Unix OS was developed for software developers. Unix has an easy-to-use CLI interface where computer commands can be sent.

Key features of the Unix command line

There are three major parts in the Unix command line, and they are:

• Command: The command is typed right after the prompt ($) in the CLI.
• Options: Options change the behavior of a command. The option usually begins with a dash (-) or two dashes (- -).
• Arguments: The arguments include one or more specific targets on which the command should operate. 

Evolution through decades

CLIs have become more efficient over the last decades. The shells have become more user-friendly, the speed has improved, and there is adequate support for scripting languages.

Advancements in CLI through the 1970s, 1980s, and 1990s 

• 1970s: Unix had the first computer command shells around the late 60s. Computers mainly worked with single-line commands entered into a command line interface.
• 1980s: Personal computers with graphical user interfaces started to become popular, leading to a decline in CLI use.
• 1990s to present: With the introduction of Apple Macintosh and Microsoft Windows, GUIs replaced CLI. However, CLIs remained relevant for system administration, programming and batch processing.

Graphical user interface vs. command line interface

Unlike CLIs, graphical user interfaces (GUIs) allow users to visually interact with their computers. GUIs have windows, scrollbars, buttons, wizards, painting pictures, and alternative icons, among other visual elements. Here is a look at how both interfaces compare.

Pros and cons of CLI

Command-line interfaces (CLIs) are fast and efficient. They use less memory and function better on slower processors. However, users need to always know complex commands, which increases the risk of errors. Also, the limited undo functionality can be frustrating.

Pros and cons of GUI

Graphical user interfaces (GUIs) are ideal for non-technical users because they provide instant visual feedback and use real-world imagery. GUIs also support various input devices. However, they usually require enormous computing power and memory. They also have some hidden commands that require deliberate searching.

Modern CLI developments

Command-line interfaces (CLIs) have improved in modern operating systems. They now work with more user-friendly interfaces. That extra versatility has also made them more accessible to non-technical users.

The complexity of modern operating systems is such that GUIs cannot completely control all system functions. So, software developers still use CLIs to automate repetitive tasks, debug code, and interact with various tools and services.

The current state of CLI in modern operating systems 

PowerShell has become the primary CLI in the Windows operating system. It allows users to run advanced scripts and automate tasks within the OS. Linux still relies on CLI, with Bash as the default shell. Bash offers extensive scripting options, which are central to Linux's flexibility.

Linux relies on the CLI, with Bash as the default shell interface. Bash provides powerful command-line tools and extensive scripting options central to Linux's flexibility and control. The Terminal app on macOS gives users a Unix-like environment, with Bash and Zsh as the default shells. It gives macOS users the same robust command-line experience in Linux and access to powerful Unix utilities.

Terminal emulators like iTerm2 for macOS or GNOME Terminal for Linux have enhanced features, such as multiple tabs, split panes, and advanced text manipulation, that ensure the CLI is more user-friendly and efficient.

CLIs have evolved in modern operating systems. They benefit from the power and flexibility of modern operating systems. It remains an essential tool for many advanced users.

Integration with other tools and interfaces

Git has many CLI commands for managing repositories, committing changes, and collaborating with teams. Docker's CLI allows developers to build, run, and manage containers, streamlining application development and deployment.

AWS CLI has a robust interface that allows infrastructure provisioning, resource management, and application deployment from the command line.

Case studies

Richie Bros

With growth came a higher demand and more development work, but Richie Bros lacked the solution to align IT and business. Contentstack's composable DXP solved the problem and helped align development and digital marketing.

Hear from the Director of Product, Michael Harker. "It's now extremely easy for the marketing team to go and change content, and that immediately flows to the website without needing any technical assistance."

Learn more about how Ritchie Bros freed up developers.

Reckitt

In the words of Paweł Płoneczka, IT&D Senior Manager Websites. “What we had was sufficient, but we couldn’t expand beyond the layer we were at.”

Reckitt needed a digital solution to support its 84 brands and 700 websites in 200 countries. Switching to Contentstack allowed them to do that. They increased website performance by 40%, reduced costs, and migrated 140 websites.

Paweł Płoneczka, further said. “With Contentstack’s global governance and control over the content model, we can make sure that all sites are compliant, have full accessibility, and work as they should out of the box.”

Read more about how Reckitt scaled multi-brand content operations across 200 markets.

Future trends in CLI

AI features like code completion and automated task generation will make CLIs more powerful and user-friendly. The increased adoption of cloud computing may also lead to more cloud-based CLIs. 

Cloud-based CLIs will ensure seamless integration with cloud-native technologies. CLIs will run side-by-side with GUIs and provide users with extra options. AI-powered CLIs will reduce the learning curve for beginners and improve human-computer interaction.

FAQ section

What is the history of CLI?

CLIs date back to the 1960s. The first one was the command-line interpreter for CTSS, followed by Multic shells and the popular Unix OS.

Which operating system historically has a command-line interface?

Unix has a command-line interface, allowing users to send commands on the go.

What is the command-line interface?

The command-line interface is a computer window that allows users to run computer commands. 

Who invented the CLI?

It is difficult to attribute the creation of CLIs to a single person. Several people have contributed to their evolution, including Ken Thompson, who developed the V6 shell, and Steve Bourne, who created the Bourne shell.

Learn more

Command line interfaces have changed from complex, hard-to-access control rooms in computers. Today, they are important parts of different operating systems. With CLIs, you can run and schedule commands and access important computer files.

The Contentstack CLI allows you to perform common tasks within the composable DXP. It works for macOS, Windows and Linux environments. Talk to us today to learn more.