What is Web Assembly?
Web Assembly or WASM is a new type of code that runs in the modern web browsers. Web Assemblies is the binaries (or bytecode) produced as a result of compiling the code written by the developer in other languages like C, C++, Dart, .Net etc.
Environment required for Web Assembly
WASM has been standardized for all major browsers supporting it in their latest versions.
The WASM apps run in the browser’s sandboxed environment which makes it safer to run being it a near machine level code from getting access to other system specific data. Each browser runs a virtual machine (VM) internally to run the WASM apps.
The older versions of browsers that do not support WASM can also run these apps using asm.js which provides backward compatibility to the Web Assembly applications.
The major difference between the two of that:
Also, since the compiled code (the bytecode) produces *.wasm files which are near to machine level (in binary format), so WASM has a massive advantage of performance over JS.
In the worst case, it can give up to 3x performance gains
In the best case, it can give up to 20x performance gains