This material was originally taken from training materials developed by the University of Southampton Research Software Group, which are based on the [software carpentries course "Version Control with Git".

This material was originally taken from training materials developed by the University of Southampton Research Software Group, which are based on the [software carpentries course "Version Control with Git".

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Version Control

Version control (or VC for short ) can also be called revision control or source control. The simplest description is that VC is a tool that tracks changes to files. It’s like turning on “Track Changes” in Word or Google Docs, but for code. So why would you want to do that?

Nothing that is committed to version control is ever lost, unless you work really, really hard at it. Since all old versions of files are saved, it’s always possible to go back in time to see exactly who wrote what on a particular day, or what version of a program was used to generate a particular set of results.

As we have this record of who made what changes when, we know who to ask if we have questions later on, and, if needed, revert to a previous version, much like the “undo” feature in an editor.

When several people collaborate in the same project, it’s possible to accidentally overlook or overwrite someone’s changes. The version control system automatically notifies users whenever there’s a conflict between one person’s work and another’s.

Teams are not the only ones to benefit from version control: lone researchers can benefit immensely. Keeping a record of what was changed, when, and why is extremely useful for all researchers if they ever need to come back to the project later on (e.g., a year later, when memory has faded).

Version control is the lab notebook of the digital world: it’s what professionals use to keep track of what they’ve done and to collaborate with other people. Every large software development project relies on it, and most programmers use it for their small jobs as well. And it isn’t just for software: books, papers, small data sets, and anything that changes over time or needs to be shared can and should be stored in a version control system.