What are Git and GitHub?
In 2005, Linus Torvalds, the creator of Linux, needed to replace the version control system used to manage the source code of the Linux kernel. He, and the Linux community, created Git. Some of the goals of the new system included:
- Speed
- Simple design
- Strong support for non-linear development (thousands of parallel branches)
- Fully distributed Able to handle large projects like the Linux kernel efficiently (speed and data size)
Git is a distributed version control system, or DVCS, that tracks the history of changes as people and teams collaborate on projects together. As developers make changes to the project, any earlier version of the project can be recovered at any time. In a DVCS, every developer has a full copy of the project and project history. Unlike once popular centralized version control systems, DVCSs don’t need a constant connection to a central repository.
Git is distributed
- Nearly every operation is local
- In centralized version control system (CVCS), you must connect to the central store to access and update the history. With Git you have the entire history of the project right there on your local disk, most operations seem almost instantaneous.
- This also means that there is very little you can’t do if you’re offline. If you get on an airplane or a train and want to do a little work, you can commit to your local copy until you get to a network connection to upload. If you go home and can’t get your VPN client working properly, you can still work.
Git is safe
Integrity
- Git uses SHA-1 hashes of data to verify integrity
- The SHA-1 hash is used to identify every object in the database
Git only adds data
- Nearly every operation adds information to the database
- It’s nearly impossible to delete anything
- This allows you to easily recover a previous state
What is GitHub?
GitHub hosts Git repositories and provides developers with tools to ship better code through command line features, issues (threaded discussions), pull requests, and code review. GitHub builds collaboration directly into the development process. Work is organized into repositories where developers can outline requirements or direction, set expectations for team members, and use pull requests to manage changes and feedback. This makes it easy to collaborate across teams and keep everyone on the same page.
GitHub is a platform that:
- Hosts Git repositories in the cloud
- Provides a web interface for browsing repositories
- Enables collaboration through pull requests and code reviews
- Offers issue tracking and project management tools
- Supports team workflows with permissions and access controls
(source: GitHub Docs)