LuaJIT is a Just-In-Time Compiler for the Lua programming language.
LuaJIT is based on the Lua 5.1.x virtual machine and bytecode interpreter from lua.org. It compiles bytecode to native x86 (i386+) machine code to speed up the execution of Lua programs.
Coco is a Lua 5.1 extension for True C Coroutine semantics.
Coco is developed as a dependency of LuaJIT, however it can be used as a standalone project. The standalone release is a patchset against the standard Lua distribution.