In the past years, all browser vendors have shipped new versions of Safari, Edge, Chrome, and Firefox, that include support for WebAssembly. And that makes all four major browsers able to run code compiled to the wasm format on the web.
“WebAssembly or wasm is a low-level bytecode format for in-browser client-side scripting, evolved from JavaScript. Its initial aim is to support compilation from C and C++, though other source languages such as Rust are also supported.”
Wasm was supposed to provide a method to deliver JavaScript code compiled as highly-optimized bytecode. The main advantage was that bytecode is multiple times smaller than the code from which it’s been compiled, this will save bandwidth on mobile devices, and help improve page loading speed.
WebAssembly is also simpler to read for browsers, giving a more structured data format and faster code parsing times. It also enables developers to write code in C, C++, or Rust, and compile it to wasm directly.
You can also try WebAssembly Explorer, which is an online tool that enables you to play around with a C/C++ compiler and learn how WebAssembly code is created, delivered, and ultimately used by the browser.