WebAssembly
WebAssembly
A technology for running programs at high speed in a web browser
In Simple Terms
WebAssembly is a technology for running programs at high speed in a web browser. Programs are converted in advance into a special format that browsers can load efficiently. Because you can convert programs written in other programming languages and run them in the browser, even demanding tasks like 3D games and video editing software become possible right in the browser. JavaScript handles things like screen interactions, while WebAssembly takes care of the heavy computation — the two work together as a team.
Behind the Name
The name combines "Web" with "Assembly" — a term for a low-level, compact set of instructions that sits closer to how a computer processes things than what humans typically write. The idea behind the name is a compact program format designed to be efficiently loaded and executed in a web browser.
Take a Closer Look!
WebAssembly is a technology for running programs at high speed in a web browser.
It is also commonly abbreviated as "Wasm."
JavaScript has long been the go-to programming language for making web pages work.
While JavaScript can handle a wide range of tasks, especially heavy operations like video processing, 3D graphics, or complex calculations can sometimes demand higher performance.
This is where WebAssembly comes in: programs are compiled in advance into a binary format that browsers can load efficiently, which often allows them to run faster than if everything were handled by JavaScript alone.
Another key feature is that code written in other programming languages — such as C or Rust — can be compiled to WebAssembly and run directly in the browser.
This makes it possible to run demanding applications like full-scale 3D games or video editing software smoothly in a web browser.
WebAssembly is not a replacement for JavaScript — the two are designed to work alongside each other.
You can let JavaScript handle user interface interactions while offloading heavy background computation to WebAssembly.