What is Web Assembly and Will it replace Javascript ?

What is Web Assembly ?

WebAssembly, also known as wasm, is a binary instruction format for a stack-based virtual machine. It is designed as a portable target for the compilation of high-level languages like C, C++, Rust, and many others. WebAssembly is intended to be a low-level bytecode that runs on the web platform, and it provides a portable target for the compilation of high-level languages like C, C++, and Rust. It aims to enable a new class of web applications, which are computationally intensive and can run at near-native speeds.

Here is an example of WebAssembly code written in C and compiled to wasm using the Emscripten compiler:

#include <stdio.h>

int main() {
  printf("Hello, WebAssembly!\n");
  return 0;
}

To compile this C code to WebAssembly using Emscripten, you would run the following command:

emcc hello.c -o hello.html

This will produce two files: hello.html, which is a simple HTML file that loads the WebAssembly module and runs it, and hello.wasm, which is the compiled WebAssembly binary module.

To run this WebAssembly module in a web page, you would include the following JavaScript code:

const response = await fetch('hello.wasm');
const bytes = await response.arrayBuffer();
const { instance } = await WebAssembly.instantiate(bytes);
instance.exports.main();

This code fetches the wasm module, instantiates it, and calls the exported main function, which will print "Hello, WebAssembly!" to the console.

Will Web Assembly Replace Javascript ?

WebAssembly is a relatively new technology that has emerged as a promising alternative to JavaScript. It is designed to provide a low-level virtual machine that can execute code at near-native speeds, making it an ideal choice for computationally intensive applications. However, while WebAssembly is powerful, it is not intended to replace JavaScript entirely.

WebAssembly is primarily intended for use in specific situations where performance is a critical requirement, such as in gaming, scientific simulations, and machine learning. It is particularly useful for tasks that involve large amounts of data or complex computations. For example, WebAssembly could be used to run a game engine or to execute machine learning algorithms.

However, JavaScript still remains the primary language for developing web applications. JavaScript has a wide range of libraries, frameworks, and tools that make it easy to develop sophisticated web applications. Furthermore, JavaScript can be executed in any web browser, making it a universal language that can be used by anyone, regardless of their browser or device.

In conclusion, while WebAssembly is a promising technology that can provide significant benefits for specific use cases, it is not intended to replace JavaScript entirely. Instead, WebAssembly and JavaScript will likely coexist, with each being used in situations where it provides the most value.