and parts of other applications or full applications such as ZeroVM.

The general concept of NaCl (running native code in the web browser) has been implemented before in ActiveX, but NaCl runs content in a sandbox while ActiveX application has full access to the system (disk, memory, user-interface, registry, etc.). Mozilla proposed asm.js as an alternative to both ActiveX and NaCl. asm.js also allows applications written in C