I've been using (and recently, contributing slightly to) Git for well over a decade. I don't have any single thing I'd specifically recommend at this point, but if you're looking for a decent book on Git, the Pro Git book has a bunch of plus-es: it's on line and kept up to date, it's free, and it's correct (unlike far too many online tutorials). There is also Think Like (a) Git, which covers most of what's missing from Pro Git.

References Garrison, D. Randy, Terry Anderson, and Walter Archer. “Critical inquiry in a text-based environment: Computer conferencing in higher education.” The internet and higher education 2, no. 2-3 (1999): 87-105. Orlov, George, Douglas McKee, James Berry, Austin Boyle, Thomas DiCiccio, Tyler Ransom, Alex Rees-Jones, and Jörg Stoye. “Learning During the COVID-19 Pandemic: It Is Not Who You Teach, but How You Teach.” NBER Working Paper 28022 (2020). Rienties, Bart, and Bethany Alden Rivers. “Measuring and understanding learner emotions: Evidence and prospects.” Learning Analytics Review 1, no. 1 (2014): 1-27.

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