What is WebAssembly?
WebAssembly, or Wasm, is a technology that allows web browsers to run code written in languages other than JavaScript, which is the traditional language for web development. Why is that important? It allows developers to run code written in languages like C, C++, Rust, and others (which are often faster and more powerful than JavaScript for certain tasks) in web browsers at speeds close to native applications.
Right now, WebAssembly supports C/C++, with a new backend being developed in clang/LLVM to support projects like Emscripten and PNaCl. In the future, WebAssembly will support more languages and other compilers, such as GCC, might also get on board.
Benefits of WebAssembly
Efficient
The Wasm stack machine is designed to be compact and quick to load. WebAssembly aims to run as fast as native code by taking advantage of common hardware features found in many devices.
Its binary format can be decoded more than 20 times faster than JavaScript can be read, according to tests. On mobile devices, large code files can take 20-40 seconds to load, so fast decoding, along with techniques like streaming for better compression, is crucial for a smooth user experience when a page is first loaded.
Safe
WebAssembly provides a secure, isolated environment to run code, which can even be built into existing JavaScript engines. When used on the web, it follows the same security rules and permissions as the browser.
User friendly / Debuggable
WebAssembly can be shown in a readable text format to make it easier to debug, test, experiment, optimize, learn, teach, and write programs manually. This text format is what you’ll see when looking at the source of Wasm modules on the web.
Part of the open web platform
WebAssembly is built to stay up-to-date and work with old versions. WebAssembly modules can interact with JavaScript and use browser features just like JavaScript does. WebAssembly can also be used outside of the web.
WebAssembly is meant to work alongside JavaScript, not replace it. While WebAssembly will allow many programming languages to run on the web, JavaScript will still be the main dynamic language used. WebAssembly and JavaScript will often be used together in different ways:
- Full C++ apps that use JavaScript to connect parts.
- Websites with HTML, CSS, and JavaScript for the user interface, and WebAssembly for the main content.
- Mostly HTML, CSS, and JavaScript apps with some WebAssembly parts for tasks like graphing or video processing.
In the future, WebAssembly will be able to work directly with JavaScript objects, making them easier to use together.
Uses of WebAssembly
High-performance web apps
WebAssembly is mainly used to create high-performance web apps that need a lot of resources, like complex calculations, simulations, data processing, and real-time 2D/3D graphics rendering.
Cross-platform mobile apps
As progressive web apps (PWAs) and hybrid app frameworks grow, Wasm allows developers to build mobile apps in high-level languages and turn them into Wasm for mobile browsers. This makes it easy for developers to reuse and integrate their existing code into web apps.
Server-side applications
Developers can use Wasm to move heavy tasks from the server to the user’s browser. This reduces the server’s workload and makes the app run more smoothly.
Web games & VR Experiences
It lets developers create complex and attractive games that run well in web browsers. With Wasm’s performance boost, developers can build immersive web games and VR experiences that used to be possible only with native apps.
Multimedia Processing
Wasm is great for handling multimedia tasks like editing audio and video, processing images, and streaming media in real-time. Developers can use Wasm to make things like video conversions, image effects, and real-time audio work faster, giving users a smoother experience with media-heavy apps.
Takeaway
WebAssembly has a promising future and is likely to become a key part of web development. As browsers and tools improve, Wasm will be used more widely, with its speed helping developers create advanced web apps that run almost as fast as native software.