A new language called WebAssembly is opening the door to the next generation of browsers

A still frame from a moving, generated landscape inside a browser using WASMIf you think of the online world as browser experiences versus app experiences, get ready to redraw your boundaries.
Mozilla, Google, Microsoft, Apple and others are excited about a newly emerging open programming tool that could help to radically transform web browsers into platforms for app-like experiences.
Called WebAssembly (WASM), it’s an assembly language for browsers that allows developers to write their applications in the popular C/C++ and then compile them for use in browsers.
This means:
dramatically decreased downloading times, so complex experiences — even highly detailed video games — can be quickly downloaded into a browser.
and much faster performance than HTML and JavaScript, although it can work alongside them.
The increase in performance is so great that major game-oriented software firms like Epic and Unity are experimenting with WebAssembly to re-create some of their challenging experiences inside a browser. Here’s a sample of videogame-like generated scenes running in a WASM-compatible browser:
https://www.youtube.com/watch?v=TwuIRcpeUWE
Shortly after WASM was publicly announced in June of 2015, developer and author Eric Elliott posted about what it meant for online software creation:
We need WebAssembly because as flexible as JavaScript is, it’s still too hard to express many of the things we may want to in JavaScript, and the features we’d need to make it easy might add complexity to a language that already confuses many users.
WebAssembly gives us access to a set of low level building blocks that we can use to construct just about anything you can imagine.
… [what] some of us have really been missing is the ability to write most of the code in an amazing high-level language and still be able to drop down to a specialized, bare metal assembly language once in a while when we really need a boost.
And a video from Mozilla presents developers’ enthusiasm for the emerging tool:
https://www.youtube.com/watch?v=MaJCfdmr9Wg
WASM is already supported by two major browsers (Chrome and Firefox), as well as the test version of one of the four major browser engines (WebKit).
Mozilla Senior Engineer Luke Wagner pointed out to me that WebAssembly may be the first standards-based technology that began with the makers of the four biggest browsers at the table — Mozilla (Firefox), Google (Chrome), Apple (Safari) and Microsoft (Edge). An active W3C working group is currently engaged in making it a full standard.
Another browser-based technology — Progressive Web Apps (PWAs) — has also been doing its best to blur the line between browser and app experiences. Mozilla’s Director of Platform Product Management Martin Best told me that WASM can be used in conjunction with JavaScript to create higher performance experiences in PWAs than JavaScript can accomplish by itself.
He added that initial tests show WASM-built experiences can recreate as much as 80 percent of the performance of a native application, on a mobile device or on a desktop/laptop, but in a browser. And, of course, it’s still early in WASM’s life cycle.
Previously, functionality was often added to browsers through plugins. WebAssembly can provide that additional functionality but without plugins’ downloading requirement or security issues, even for such processing-intensive uses as video encoding, video games and image editing.
Mobile users are downloading fewer and fewer apps, and discovering new apps in app stores is an increasingly frustrating challenge. WebAssembly, PWAs, the coming of 5G mobile speeds and other developments are pointing to the day when the browser is not just the display window for web pages, but a fully realized portal into immersive experiences.