What Is Version Control? How It Works

Have you ever saved your resume to your computer as “resume2023” or “resume final version?" Whether you know it or not, you’re practicing version control—a system of organizing revisions to a document to track changes. Version control is important in various applications, however, it’s most commonly connected to computer programming and software engineering.

Version control allows a document to be reverted to its original, unedited version. It allows multiple people to work on a project simultaneously without interfering with each other’s work, and it’s an essential skill for software programmers and DevOps. 

Learn more about how version control works, the different types, and who uses it.

What is version control?

Version control refers to the system of tracking changes in a document so that it's possible to see what changes your team made at any given project stage. Like the resume example above, version control can be as uncomplicated as a series of file naming conventions. You could easily select the most recent or a past version you’d like to review.

When it comes to software development and managing a large team—especially one working simultaneously on code—version control is crucial and more sophisticated than file names. Multiple developers can work out bugs, update codes, and test new software features at the same time using version control to separate their work until it’s ready to combine. Collaboration tools like Dropbox and Google Drive have built-in version control tools, while many developers use software like GitHub to manage version control. 

Why is version control important? 

Version control is important because it organizes creative work for a project and allows large teams to simultaneously collaborate in code. Each person working on code can store their changes in a branch separate from the rest of the code, meaning that the changes each person makes won’t integrate into the main file until they’re completed, analyzed, and approved. Version control keeps coding projects organized and productive, ensuring that the development of a project is on-task.

3 other version control benefits

Version control allows large teams to collaborate on complex projects. Other benefits of version control include revision history, automated backups, and a central repository that supports secure testing and experimentation. Below, we’ll explore each of these advantages in more detail.

1. Revision history

Revision history allows you to see your team's changes, at what time, and who made them. Each time anyone makes changes, a new version of the file is saved to the repository's branch. If something goes wrong with the code, you can review the changes to see when it was working properly. 

2. Automation features

Version control programs sometimes contain features for automating tasks such as analyzing and testing code. Automating tasks can save time by cutting out repetitive tasks. 

3. Central repository

A central repository is the main, approved code held in a single location where everyone can access it. People accessing the code can make changes, test new features, and experiment safely without damaging the main code. The new changes will only integrate into the main code once the team has tested and accepted the changes. 

How does Git work?

Git is an open-source version control system hosted on platforms like GitHub. Within Git, each project has a central repository where Git stores the data. Users can copy sections of the code to a working directory where teams can edit, update, or experiment with them. This method, called branching, protects the main code while allowing developers to experiment with new things. It also helps to keep the main code working while teams are coding behind the scenes. 

Once you’re ready to save the file, the program creates a new commit—or save point. Then, when the team is ready to update the software, they can push the changes into the main code. You can store Git locally or on a platform to access it remotely. 

Version control types

Three of the most common version control types are local, distributed, and centralized. 

Local

Local version control happens when all changes are stored on a single computer. The benefit of local version control is simplicity, as it’s the least complex of these three version control types. The limitations of locally distributed version control are that you must be physically present at the location to work on them, and collaboration can become challenging as only one computer holds the latest version.

Local version control works best for solo programmers, graphic designers, or other independent creative professionals who work on the same computer daily and don’t require much functionality for collaboration.

Distributed

A distributed version control is one where the main repository is stored in one location, and many different people can access the software simultaneously, pulling a clone of the code into their own local storage while they make changes. Distributed version control enables larger teams to collaborate, but the data stays isolated until it's uploaded to the central repository. While this encourages experimentation, it can hinder real-time collaboration.

Centralized

In a centralized version control system, the code is stored in one place. Every change made to the code is automatically stored in branches, waiting to be integrated into the main repository. Centralized version control is effective for collaboration because you can see other people’s work in real-time. 

The limitations of a centralized version control system are that in case of an interruption in access to the internet, no one on the team will be able to access the code. It can also be more difficult to publish updates to the code because it’s more likely that a programmer is working on something at any given time. Also, a corrupted server without a saved history could corrupt the entire project because one server stores everything.

Who uses version control?

Software developers, software engineers, and other team members creating software, video games, or applications use version control daily. Version control is also useful for creative professionals like graphic designers or writers.

Getting started on Coursera

Building skills with version control can make you a stronger candidate for software or game development careers. If you’re ready to learn more, consider the course Version Control With Git offered by Atlassian University on Coursera. This course will take approximately 13 hours to complete and can help you build skills with version control, command line interface, GitHub, and Bitbucket.