3 great Git alternatives: Fossil, Mercurial, and Subversion
Git started life as version control software developed to manage the source code for the Linux kernel. It's since become the default, go-to tool for managing source codebases for just about every open source project—and many closed-source ones, too.
For all its popularity, Git also draws deep and legitimate complaints. It has a complex model for how code is staged, maybe too complex for its own good. Its command set can be confusing. Unfortunately, GUIs and front-ends just mask the underlying complexity rather than solving the underlying problem. Git also does not do well with certain kinds of files that are tracked in open source projects, like large binaries and complex data structures.