From ASM.JS to WebAssembly
Today I’m pleased to announce that cross-browser work has begun on WebAssembly, a new intermediate representation for safe code on the Web. WebAssembly, "wasm" for short, .wasm filename suffix, a new binary syntax for low-level safe code, initially co-expressive with asm.js, but in the long run able to diverge from JS’s semantics, in order to best serve as common object-level format for multiple source-level programming languages.
Source: brendaneich.com