In simple words, Version Control systems are software tools that help a software team to manage changes to source code over time. These are also known as revision control or source control systems. This article is about what is version control, it’s benefits and the different types of version control systems.
What is Version Control Systems?
Software developers working in teams are continually writing new source code and changing existing source code. The code for a project is typically organized in a folder structure. One developer on the team may be working on a new feature while another developer fixes a bug by changing code, each developer may make their changes in several parts of the folder structure.
This is where Version Control comes into action. So, a Version control software actually keeps track of every modification that you do to the code in a special kind of database. If a mistake is made, developers can easily turn back the clock and compare earlier versions of the code to help fix the mistake while minimizing disruption to all team members.
Without a version control system, you will often run into problems like not knowing which changes that have been made are available to users or the creation of incompatible changes between two unrelated pieces of work that must then be painstakingly untangled and reworked.
Benefits of version control systems
- Maintain multiple versions of the code
- An ability to go back to any previous version.
- Developers can work in parallel and across the globe.
- Find out the difference between versions.
- Provides backup without occupying much space.
- Review the history of the changes.
Types of Version Control Systems
Version Control Systems can be divided into two classes:
- Centralized Version Control System (CVCS)
- Distributed Version Control System (DVCS)
The Centralized version control systems are based on the idea that there is a single “central” copy of your project. So, everyone requests the latest version of your work and pushes the latest changes to this central copy. This literally means that everyone sharing the server also shares everyone’s work.
Whereas on a Distributed VCS, everyone has a local copy of the entire work’s history. This means that it is not necessary to be online to do the updates. Also, in DCVS, the developer make changes in his/her local repo, which he/she can share with other developers. So, there isn’t a central entity in charge of the work’s history in case of DVCS. Anyone can sync with any other team member. This helps avoid failure due to a crash of the central versioning server or system.
Few Popular Version Control Systems
CVS – The grandfather of revision control systems. It was first released in 1986
SVN – Subversion(SVN) is probably the widest adopted version control system. It is an example for Centralized Version Control System. Most opensource projects use Subversion as a repository. SourceForge, Apache, Python and Ruby are some of the major projects using SVN as the repository.
Git – Git is the new fast-rising star of version control systems (DCVS). It is initially developed by Linus Torvalds(The creator of Linux) and It has recently taken the Web development community by storm. With a distributed version control system, there isn’t one centralized code base to pull the code from.
Mercurial – Mercurial is another open-source distributed version control system. Mercurial is extremely fast and was actually designed for larger projects, most likely outside the scope of designers and independent Web developers.
Bazaar – Bazaar is yet another distributed version control system, similar to Git and Mercurial. It has a very friendly user experience. It calls itself “Version control for human beings.” Also, it supports many different types of workflows, from solo to centralized to decentralized, with many variations in between.
We will discuss the working of some of these Popular Version Control Systems on our future posts.