Through Anselm Hannemann's newsletter 'Web Development Reading List' I found this very informative and easy to follow step-by-step guide to Git:

The goal of this book is to get you started with version control and Git as quickly and easily as possible. Unlike other books about this topic, this one doesn't require a master's degree in computer science to read it. It's aimed at beginners of programming, at designers, at project managers... It tries not to require too much prior knowledge on the technical side. It tries to go

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