WebAssembly is the latest code that can be run in modern web browsers. WebAssembly (abbreviated Wasm) is a stack-based virtual machine binary instruction format, according to webassembly.org. Wasm is a portable target for high-level languages such as C/C++/Rust compilation, allowing client and server programs to be deployed over the web.

The name “stack machine” should not be a deterrent. The concept underpinning how Wasm code operates is called a stack machine in this context. It’s primarily a browser-based virtual machine for running C/C++ and Rust.

WebAssembly, in general, allows you to run code written in a variety of languages at near-native speeds on the web. Wasm can also be thought of as a compilation target for current C/C++ or Rust projects that want to run in a web browser.

The Abstract Syntax Tree (.wasm file extension) is defined using web assembly code. This code may be written, inspected, and debugged by hand thanks to a human-readable text format (the definition for which is still being finalized). Furthermore, the binary format produces a significantly smaller bundle than JavaScript, allowing for speedier payload delivery.

WebAssembly’s Key Concepts

The following are the key concepts:


A module is an item that the browser compiles into machine code that may be executed. A stateless module is one that can be shared between windows and web workers.


In WebAssembly, memory is an array buffer that stores data. The JavascriptapiWebAssembly.memory can be used to allocate memory ().


The table is a typed array in Wasm that is stored outside of WebAssembly memory and contains largely references to functions. It keeps track of the functions’ memory addresses.


An instance is an object that contains all of the exported functions that may be invoked from javascript and run within the browser.

What’s the difference between WebAssembly and JavaScript?

Because Javascript is a text-based language, but Wasm is a binary-based language, it is well-suited to low-level computation. With this in mind, we now have the ability to create bizarre web-based features that we previously only imagined. That’s why I think of WebAssembly as a supercharged version of JavaScript.

It’s also worth noting that Wasm isn’t meant to replace JavaScript. Instead, it’s meant to be used in conjunction with JavaScript, allowing programmers to take advantage of both languages’ advantages. I would never recommend writing web components in Wasm, for example.

Similarly, JavaScript may be difficult, if not impossible, to express features involving raw bit manipulation. Furthermore, JavaScript has grown in popularity in the web development community, with a large ecosystem of frameworks, libraries, and tools available.

Wasm is not always quicker than JavaScript in terms of performance. Wasm will be a full game-changer in terms of performance once it can ship parallel processing pipelines like threads and SIMD (Single Instruction, Multiple Data).

What can WebAssembly be used for?

3D gaming, virtual and augmented reality, computer vision, image/video editing, and other applications that require native performance are well-suited to Wasm. Web Assembly will effectively fill in the gaps for things that were previously unavailable in browsers, as well as increase their capabilities.

In addition, Wasm will make it easy to stream large amounts of data across a network of processing algorithms. So, many best web development companies in Chennai are using WebAssembly.We used Wasm to build the majority of the backend, which gave our web application a serverless feel.

Assume you want to use a C-based compression package in your web application. You may start by porting the complete library to JavaScript and then importing it into your web app.

That’s a difficult task, and I wouldn’t trust inexperienced readers to take part in it. Wasm is useful in this situation. Now all you have to do is convert the library to Wasm, and you’re done! For your web application JavaScript code, you can use the full library (WebAssembly modules) with no effort.

How can I use WebAssembly?

There are four main ways to use WebAssembly modules in your application:

  • WebAssembly code translation from C
  • Manually writing or creating WebAssembly code.
  • Writing Rust code with WebAssembly as the goal output.
  • AssemblyScript is a syntax that is quite similar to TypeScript and readily compiles to WebAssembly.

Only the first option will be discussed in this post.

Assume you wish to convert a C program to WebAssembly. You can use internet tools or Emscripten to perform it on your local system.

Emscripten is an LLVM-based toolchain that compiles your C source code into a.wasm module, as well as the JavaScript “glue” code needed to load and operate that module using the WebAssembly JavaScript API. It also creates an HTML file that displays the result by loading the JavaScript “glue” code.

Here’s a quick rundown of the toolchain:

Your C source code is compiled into LLVM’s intermediate representation using Clang.

On such intermediate representation, LLVM performs some optimization.

Emscripten translates the LLVM’s IR to a.wasm module using a backend tool named asm2wasm.

Emscripten comes with a number of tools that make it possible to fully transfer huge C/C++ codebases to WebAssembly. In fact, it uses SDL and OpenAL technologies, as well as IndexedDB to simulate a file system. Emscripten, rather than being a compiler, can be thought of as a full-fledged SDK.


WebAssembly, or WASM, is a binary code format that is similar to assembly but is independent of the language and platform because it can be compiled from other languages and run in a browser (Web APIs) or on a virtual machine. WebAssembly is an open standard whose major goal is to provide web performance that is as near to native as possible while being compatible with current ecosystems and standards.

The purpose of this article is to provide a high-level overview of WebAssembly. Feel free to go deeper into this fascinating technology, and I hope that this post provided just enough information to get you started experimenting with WebAssembly in your own projects.