Other
Library vs Framework
A library is a collection of functions to solve a specific problem within your code structure while a framework dictates how to structure your code.
Monorepo vs Polyrepo
The difference between a mono-repo and a poly-repo is that a mono-repo contains everything, even if the codebase contains different products written in different languages. A poly-repo splits the code base up over multiple repositories, most often on a product-by-product basis.
I have professional experience in both and from that experience, I lean more toward a mono-repo. Funnily enough, I was very opposed to the idea of having everything in a single repository at first, but after using it for a while, I started seeing the advantages. This website is also structured as a mono-repo. One of the downsides you often hear is that you need a lot of tooling for a mono-repo to work well, from my personal experience, working in a poly-repo requires a lot of tooling as well. Keeping the boundaries between code also enables code sharing and lowers the boundary to contribute to other code.