Today’s Web Technology

Today’s web is a veritable playground for developers. You have the luxury of easy access to broadband speeds (with exceptions). Browsers are faster and more powerful than they’ve ever been, and the workstations people use to run those browsers have oodles of RAM, storage, and multiple cores—even the mobile devices.

Today’s JavaScript is nothing like the primordial 1995 JavaScript that drew so much ire from the developer community. It dominates the web development landscape so much that its own ubiquity has become something of a joke or a meme. Competition between browser vendors (they didn’t call it the browser wars for nothing) has spurred years of refining the way their products execute JavaScript, which will be a key discussion point when you get into the details of browser-hosted WebAssembly.

Modern browsers have virtual machines responsible for JavaScript execution. Internally they optimize and produce a form of bytecode from processed JavaScript. This, coupled with more memory and processing power, means that JavaScript is actually fast. Not just a little bit fast, but it’s so fast you can play full, grade-A video games in the browser. Applications can perform complex calculations, run machine learning models, process vast amounts of data, and otherwise treat the browser like an operating system.

Frameworks like React, Angular, Backbone, VueJS, and countless others have made a dramatic impact on how web applications are built. Modern web applications can render incredibly dense user interfaces like what you see on Facebook or YouTube, all while receiving real-time events published from servers in the cloud to provide a level of interaction that’s now such a ubiquitous feature that web sites that don’t provide this new level of real-time interaction are often publicly shamed and doomed to fail.

Nothing in the rest of this book that extols the virtues of WebAssembly should take away from the fact that the modern, programmable web is a giant virtual toy store, ripe for the plundering by eager developers. For any avid learner of technology, it’s a great time to be alive (and probably learn some JavaScript).