there are legitimate technical reasons for using NPM (disk is cheap, project local packages ftw, etc.). gem, less so. I can, however, tell you the primary reasons for using npm or gem: I need a dependency, my os hasn&#x27;t packaged it, and it&#x27;s the path of least resistance.<p>Also, I am a hobbyist programmer. I also know that git was created by Linus Torvalds, it&#x27;s a DVCS (although Torvalds calls it an SCM), and it&#x27;s based on a DAG (directed acrylic graph), which is a directed graph with no directed cycles, and excellent for modelling causal relations. I can explain to you the difference between a rebase and a merge. I know that git uses SHA-1 hashes to identify check-ins internally, as a data security feature. I know that checkins and other objects are stored in the .git folder at the repository&#x27;s root directory. I know that these objects are garbage collected, although the frequency at which they are escapes me. I know that, despite common belief, git commits are immutable, but also that the git history is not. I know that git was inspired by BitKeeper, after the incident that caused the linux source to be moved away from that system, because Linux got fed up with tarballs and patches, and hates CVS with a fanatical passion. I know that git had three design goals: distributed, fast, and guarantees that you get the same bits out that you put in. And I&#x27;ve have several years of causal experience with git, using probably one tenth of its functionality.<p>I may not be able to recite git&#x27;s internals at you, but I know it&#x27;s features (to an extent), I know the tools, and I know the reasoning. And the functionality sure as heck isn&#x27;t magic.