Introduction to WebAssembly: Why Should We Care?

There is a new weapon in the
great war against JavaScript the struggle to allow developers to choose their favorite style of programming while improving performance and their productivity. That weapon is WebAssembly, and it will revolutionize client-side web development.
WebAssembly, or wasm, is a low-level bytecode format for in-browser client-side scripting. If you are writing a compiler for a programming language one option is to target a platform, like the JVM or .NET, and compile your language to the target bytecode. WebAssembly occupies the same role, so when you are compiling to WebAssembly you are making your software available for all platforms where it is supported, in other words, all browsers.