How browser games stopped needing plugins
For about fifteen years a browser game meant Flash, a plugin, and an update you kept clicking "later" on. Then browsers quietly learned to do it all themselves.
If you played web games in the 2000s, the game wasn't really running in your browser. It ran in a plugin, usually Flash, sometimes Java or Shockwave, and the browser just lent it a rectangle on the page.
What Flash got right
It drew fast, played sound reliably and behaved the same on every computer. It also came with an editor that let people who couldn't program make things move, and a huge amount of the old internet's weird creativity came out of that. Browsers at the time couldn't draw freely, play sound properly or animate smoothly, so for games there wasn't another option.
What ended it
Phones, mostly. The iPhone never ran Flash, and a growing share of players simply couldn't open the games. Security didn't help either: a plugin is a separate program running content from strangers, and keeping it patched was a constant chore. Meanwhile browsers caught up, slowly and without much fanfare, until the plugin wasn't needed.
What replaced it
A canvas. The <canvas> element is a rectangle of pixels a
page can draw into. It sounds basic, and it's quick. Every game here draws into one.
Strata goes one step further and uses WebGL, which talks to the graphics card directly, because it has a lot of tiles and lighting to draw every frame.
Sound made in code. Browsers include a small synthesiser, so a game can make its sounds as it goes instead of downloading audio files. Several of our games don't ship a single sound file, and it means a sound can follow what's happening, like an engine note that tracks your actual speed.
A proper frame timer. The browser tells the game when to draw the next frame, in step with your screen, and slows it right down when the tab is hidden so it doesn't eat your battery in the background.
What got lost
Nothing today is as easy for an artist as Flash's editor was. We also lost a way of sharing: Flash games were files that got passed around and rehosted. Today a browser game lives on one website, and when that website goes, so does the game.
Making one now
Honestly, it's great. Nobody installs anything, updates reach everyone instantly, and it runs on an old laptop or a phone. The hard part is controls. A keyboard game doesn't work on a phone, and touch controls feel strange on a desktop, which is why most of ours use one button or one thumb. And browsers won't play sound until you've clicked something, which is why every game starts with "tap to start".