The Git book is excellent and officially maintained. <a href="https:&#x2F;&#x2F;git-scm.com&#x2F;book&#x2F;en&#x2F;v2" rel="nofollow">https:&#x2F;&#x2F;git-scm.com&#x2F;book&#x2F;en&#x2F;v2</a><p>It serves as both a great introduction and a reference.