What is version control?

In practice, version control stores all modifications in a dedicated database. This enables developers to compare past and present versions of code, recover from errors quickly, and maintain a clear history of how a project has evolved. For DevOps teams in particular, version control shortens development cycles, reduces errors, and increases the success rate of deployments.

Version control manages changes to a project by recording updates, storing them in a repository, and making collaboration easier for teams. Here's how it works in practice:

• Recording changes – Every edit, addition, or deletion in the codebase is captured and logged with details about who made the change and when.
• Creating snapshots – Instead of duplicating files, the system saves a snapshot of the entire project whenever developers commit their work.
• Repository storage – These snapshots are kept in a repository, which acts as the single source of truth for the project's history.
• Access to history – Developers can review past versions, compare differences, and roll back to a previous state if something goes wrong.
• Collaboration support – Teams can work on the same codebase at the same time. The system merges changes and highlights overlapping edits.
• Resolving conflicts – When two developers modify the same section of code, the system flags a conflict, and a human decides how to combine the edits.

Version control is essential because it provides structure, safety, and efficiency in software development. Its importance comes from several key benefits:

◽️ Change tracking – Every modification to the codebase is recorded with details about who made the change and when. This makes it easy to review progress and understand how the project has evolved.

◽️ History and auditing – The full history of a project is preserved, providing a reliable record for debugging, accountability, and compliance.

◽️ Rollback capability – If mistakes occur, developers can quickly revert to a stable version of the project, minimizing downtime and disruption.

◽️ Collaboration – Multiple developers can work on the same project at the same time. Branching and merging workflows ensure that contributions do not overwrite each other.

◽️ Single source of truth – A central repository ensures all team members are working with the same, most up-to-date version of the project.

◽️ Safer experimentation – Developers can create separate branches to test new ideas without affecting the stability of the main codebase, fostering innovation.

◽️ Faster development – Teams can build features in parallel and safely merge them into the main project when ready, reducing development cycles.

◽️ DevOps integration – Version control underpins continuous integration and deployment pipelines, supporting automated testing, stable builds, and reliable releases.

◽️ Protection of valuables – Source code is one of the most valuable assets of any software project. Version control safeguards it from accidental loss, corruption, or human error.

A version control system (VCS) is a tool that records every change made to project files. It allows developers to go back to earlier versions, recover from mistakes, and work together on the same codebase without overwriting each other's work. By keeping a full history of changes, a VCS makes collaboration easier, improves accountability, and ensures projects can grow and evolve safely.

Version control systems can be grouped into several types, with centralized and distributed being the most common. Other approaches include lock-based and optimistic systems. Let's elaborate on them:

Distributed version control system (DVCS)
In a DVCS, every developer has a complete copy of the repository, including its history. This allows work from multiple locations, offline development, and easier collaboration across remote teams. Git is the most widely used DVCS.

Centralized version control system (CVCS)
A CVCS uses a single, central repository that all developers connect to. This setup is simpler to manage and is often used in smaller teams or projects where centralized control is preferred. Examples include Subversion (SVN) and CVS.

Lock-based version control system
In this model, files are locked when a user edits them. Locking prevents multiple developers from making conflicting changes to the same file, but it can also slow down collaboration.

Optimistic version control system
Here, each developer works in their own private workspace. When changes are submitted, the server checks whether they can be merged safely with others. If conflicts occur, they must be resolved manually.