Asm.js
asm.js is a subset of JavaScript designed to allow computer software written in languages such as C to be run as web applications while maintaining performance characteristics considerably better than standard JavaScript, which is the typical language used for such applications. asm.js consists of a strict subset of JavaScript, into which code written in statically typed languages with manual memory management (such as C) is translated by a source-to-source compiler such as Emscripten (based on LLVM).