From Flash to HTML5 Games: How Browser Puzzles Got Here

For fifteen years, a browser game meant a plugin. Then the plugin died. A plain account of what changed and why puzzles came out ahead.

If you played games in a browser before about 2012, you almost certainly played them in Flash. If you play them now, you are playing HTML5 games, whether or not anyone has used the phrase. The switch between the two was one of the bigger quiet changes on the web, and it is the reason a site like GridPencil can exist in the form it does.

The plugin years

Flash was a separate piece of software that lived inside your browser. A web page would leave a rectangle for it, and inside that rectangle Flash could draw, animate and play sound in ways that web pages themselves could not. For games it was a gift. From the late 1990s onward, entire websites were built around collections of small Flash games, and a generation learned to waste a lunch hour on them.

It had problems that were easy to ignore at the time. It had to be installed and kept up to date. It was a regular source of security holes. And it was owned by one company, so it only ran where that company chose to make it run.

The phone that would not play along

In 2007 the iPhone arrived without Flash, and it never got it. In April 2010 Steve Jobs published an open letter, "Thoughts on Flash", explaining why: battery life, reliability, security, and the fact that Flash had been designed for mice, not fingers. People argued about his motives. The practical result was not in doubt. A growing share of the world's browsing was happening on devices where Flash games were simply blank boxes.

What HTML5 actually added

"HTML5" is a loose label for a set of abilities that browsers gained around the same time. For games, three mattered most:

• The canvas. An area of the page that a script can draw on freely, pixel by pixel. This is what replaced the Flash rectangle.
• Built-in sound and video. No plugin needed.
• Storage on the device. A page can save a small amount of data in your browser, such as a high score or a list of solved puzzles.

Add faster JavaScript engines, and a web page could finally do by itself what used to need a plugin. The HTML5 specification was formally completed in October 2014. Adobe announced in 2017 that Flash would be retired, and support ended on 31 December 2020. Browsers removed it soon after.

Why puzzles did well out of it

Action games lost something in the move, at least for a while. Puzzles lost nothing and gained a lot.

A logic puzzle does not need sixty frames a second. It needs a grid, clear numbers and a tap that registers. The puzzles on this site are not even drawn on a canvas. They are built from ordinary page elements, the same building blocks as a table or a button, which means the text stays sharp at any size and screen readers have something to work with.

The other gain is reach. One version of Sudoku Six runs on a phone, a tablet, a laptop and a desktop with a monitor the size of a door. It responds to a finger or a mouse, and on a computer you can type the digits. Nobody has to download anything, and nothing asks for permission to install.

What it means for you

A few practical consequences are worth knowing:

• Nothing to install, ever. If a site offering HTML5 games asks you to download a file to play, close the tab.
• Your progress lives in your browser. The ticks beside solved puzzles here are stored on your device. Clear your browser data and they go. Use a different browser and you start fresh.
• It works offline less than you would think. The puzzle runs in your browser, but the page still has to load first.
• Old browsers struggle. Anything updated in the last few years is fine.

A small loss, honestly

Thousands of Flash games vanished when the plugin did, and some were good. Preservation projects have saved a great many, which is worth knowing if you are nostalgic.

For puzzles, though, the present is better than the past. The games load faster, work on every device and cannot do anything to your computer beyond the page they sit in. If you want to see how far that goes, open any puzzle in the list on your phone and then on a desktop. It is the same file.