Lua is well-liked because it's runs very close to C and easy to embed against, it's Algol-like, it has no dependencies beyond C itself, and it performs decently

Lua is well-liked because it's runs very close to C and easy to embed against, it's Algol-like, it has no dependencies beyond C itself, and it performs decently. It isn't as widely used as Python or Ruby because being embedded means it has a tiny standard library, and correcting that would go against the strengths of the language. (There's code and libraries out there, but it's all fragmented) That said, the community is out there, and pretty widespread.