Dev Breakthroughs

This comprehensive primer on the internal operations of WebKit and Gecko is the result of much research done by Israeli developer Tali Garsiel. Over a few years, she reviewed all the published data about browser internals (see Resources) and spent a lot of time reading web browser source code.

As a web developer, learning the internals of browser operations helps you make better decisions and know the justifications behind development best practices. While this is a rather lengthy document, we recommend you spend some time digging in; we guarantee you'll be glad you did.

The latest Firefox release includes a new tool for web developers: Scratchpad. The idea behind Scratchpad is simple: the browser is a fantastic place to experiment with JavaScript. Most JavaScript developers already know this and they use tools like the Web Console or Firebug’s command line to take advantage of the one environment that knows everything about their web page.

Tools like the Web Console are optimized for entering a single line of code. (ProTip: you can use shift-enter to put multiple lines of code into the Web Console.) Firebug has a button you can click to get into a multi-line input mode. Even with that multi-line input, the workflow is still centered around performing operations step-by-step and linearly.

Interaction with Scratchpad is quite different. It throws away the “one line of input gives you a line of output” interaction in favor of a text editor that knows how to run JavaScript.

Interesting historical aside: Scratchpad was heavily inspired by the Workspaces feature of Smalltalk environments. Thirty years in, we’re still reinventing Smalltalk ;-)