So another typed Lua, huh? What are the main differences to teal?
I actually hadn't heard of Teal! I don't think it existed when we started.
Judging from the Teal documentation, I'd venture that it looks pretty similar to Luau in everyday use.
If I were to guess, I'd venture that the biggest differences are probably the kind of type inference we do (Luau's inference engine draws inspiration in equal parts from OCaml and TypeScript), a bunch of Roblox-specific features, and that our inference engine is all C++ for performance.
I've been meaning to try out roblox for a while and lately I've been getting pretty hyped about teal (for context, the guy behind it is the creator of luarocks and htop, among others) so I might see the differences up close sooner rather than later :D
EDIT: (unrelated) Already not looking forward to people asking "Lua" questions about typing and constantly having to explain that Lua is not just a roblox thing xD
The real difference tho is age, Luau has been around since 2006 or so (used to be known as Rbx.Lua).