Since its launch in 2011, Native Client (NaCl) has provided developers with the ability to build web applications that harness the computational power of client machines to a much fuller extent than traditional web technologies, by running compiled C and C++ code securely and at near-native speeds, and taking advantage of multiple cores with shared memory.
Portable Native Client (PNaCl, pronounced "pinnacle") extends the capabilities of Native Client by letting developers build fully-portable executables that can be distributed on the open web. Users can run PNaCl applications without any installation, either of a browser plugin or of the applications themselves. In short, PNaCl combines the portability of existing web technologies with the performance and security benefits of Native Client.
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