A version control system is a type of software tool that allows a development team to track how a project has evolved over time.
It’s likely that, if you’ve spent any time researching version control systems, you have heard of either Git or SVN. Both these technologies allow you to track the history of a codebase, and are examples of version control systems.
But, what is the difference between these tools? How do they compare? To assist you in answering these questions, we have decided to write an article that compares these two different systems of version control like-for-like.
We’ll start by discussing the basics of version control and how these two technologies and how they work, then we will compare them across a few different factors to help you understand their similarities and differences.
What Is Version Control?
Git and SVN are both version control systems (VCS).
VCS software allows developers to keep track of all the modifications made to a codebase. This, in turn, allows you to see who has made what changes to a project and when. In addition, using VCS software gives you the ability to turn back the clock and see a previous version of a repository, which you can then revert back to if you want.
Because software developers often work in teams, having a single record of how a project has changed is essential, and helps to ensure the stability of a codebase as it changes.
What Is Git?
Git, developed by Linus Torvalds in 2005, is a distributed version control system. This means that Git allows you to keep a record of all the changes made to a codebase. But, unlike other tools, Git is distributed, which means that the tool does not rely on having a single record of a repository—the codebase for a project is distributed.
Using Git, developers can work on a codebase from anywhere. You can download a copy of a Git repository to your local computer, work on a project, then, only when you are ready, you can push your changes to the main version of a codebase. This means that you are not dependent on a single codebase—you can have multiple copies of your code across devices.
According to Stack Overflow’s 2017 Developer Survey, more than 70 percent of developers use Git.
What Is SVN?
SVN, which is short for Subversion, is a centralized version control system. This means that Subversion allows you to store a record of the changes made to a project, but that history is stored on a central server.
Unlike Git, which is distributed, you need to have constant access to an SVN repository to push changes. Only when a developer makes changes to a central server will they be saved.
In addition, instead of having a copy of a project’s history on your local machine, you only have a copy of the code itself. So, to see how a project has evolved, you need to reference the one central version of the codebase.
What’s the Difference Between Git and SVN?
So far, we’ve discussed the backgrounds behind these technologies. Now we are ready to ask: What are the differences between these two systems of version control?
To help make an equal comparison, we are going to discuss these tools in the context of four factors. These are as follows:
- Architecture: This point refers to whether the version control system uses a distributed or centralized architecture.
- Learning Curve: This factor discusses how easy—or how difficult—it is to learn each of the version control systems.
- Branching and Merging: This factor discusses how the branching systems work for both version control systems.
- Access Controls: This factor explores how permissions are handled on each system.
Let’s explore each of these factors individually.
The core difference between Git and SVN is the architecture behind these technologies.
Git’s architecture is based on the distributed version control system. As a result, Git is installed on a workstation and is both a client and a server.
When a developer wants to work with a Git repository—the word used for a “project” in Git—they download a copy of that repository to their computer. This allows them to work on a project without having to be connected to a central repository all the time. Then, when they want to make changes to the main codebase, they push them to the main repository.
SVN, on the other hand, uses a separate server and client. The only files stored on a developer’s local machine are those to which they are making changes; the rest is stored on the SVN server. So, in order to make changes to a SVN repository, a developer must have constant access to the server.
The Git architecture is beneficial because it is lightweight, easy to use, and reduces dependency on a central system. However, for projects with larger files, Git can become more difficult to use.
This is because using Git involves creating copies of a repository on one’s local machine, and so if a repository contains big files, it can be difficult to quickly and efficiently create a copy of a codebase. As a result, in projects with larger codebases, SVN is often favored.
Both Git and SVN have similar learning curves.
The Git version control system may have an edge on account of its ubiquity. Because so many developers use Git, there is ample documentation out there to help beginners get started in learning how to use the technology.
In addition, because Git is the version control system supported by GitHub—which is used by millions of developers, many of whom are beginners, to share their code—there is a wide developer ecosystem out there to support people learning Git.
However, Git does have a somewhat confusing syntax, which means it can take some getting used to. SVN, on the other hand, may not be so ubiquitous, but still uses a simple syntax and has a strong community of developers who support the technology.
Branching and Merging
Git and SVN approach branching and merging differently.
On SVN, branches, tags, and trunks are created as a directory inside a repository. This means that, if you want to access a branch, tag, or a trunk, you need to navigate into a particular directory. Then, when you are ready to push a change to a branch, you commit it back to the trunk.
This structure can quickly get complicated and takes time to manage.
Git, on the other hand, uses a branch system that only references certain commits. You can create and update a branch at any time, without changing the commits that are on that branch. On Git, if you want to add a new feature to a project, you can easily create a new branch, add the feature, then merge it into master.
The Git branching system, where branches only reference commits, is often considered easier to understand and manage at scale.
When you’re using SVN, you can specify different read and write access controls for each file and directory in a repository. This power is reserved for people who have specific access permissions on the central repository.
Git, on the other hand, makes the assumption that all contributors should have the same permissions. So, there is no central arbiter who controls access on a file-by-file basis—everyone has the same permissions.
Neither system is necessarily better than the other, but for smaller projects where specific access control is not required, Git’s system is often preferred.
The Bottom Line
So then, which version control system should you learn? The answer is—it’s completely up to you.
Git provides an easy-to-use version control system that is distributed and has a strong branching system that can help with source code management. In addition, Git also has a stronger following.
SVN, on the other hand, has a good access control system, a learning curve similar to that of Git, and has a few architectural benefits too.
The version control system you learn to use should be the one that you think best suits your needs.
Do you plan on working on projects with massive files? Maybe knowing SVN would be beneficial. Or do you know that you’ll primarily be using Git at work? If so, Git may be a better investment.
Both version control systems have their own best use cases, and having a knowledge of either system will give you a much clearer insight into how software projects are built.