DOM Observer
CSS Tricks
Books & Authors
Essential Elements

This commonly used mixin contains methods and properties for objects that can have a parent.

What is a ChildNode?

(It's implemented by Element, DocumentType, and CharacterData objects.)


Front-enders once employed multiple background images and nested `div`s to achieve the rounding effect possible with this one property.

What is `border-radius`?


YDKJS? The popular series of books diving deep into the core mechanisms of JavaScript is authored by this JS Party guest.


As of March, 2020 this browser commanded 4.42% of global market share

What is Firefox?


Yo dawg. Xzibit heard you liked browsing contexts. So he used this element to put a new browsing context inside your browsing context so you can browse contexts while you browse contexts.

What is <iframe>?


This is the state of a failed Promise. It better have a good reason.

What is rejected?

(A pending promise can either be fulfilled with a value, or rejected with a reason (error))


Floated objects do not add to the height of the object they reside in properly. To fix it, one must...

What is clear the floats?


Not just for web devs! The authors of this famous programming book were also co-signers of the agile manifesto. 

What is the Pragmatic Programmer by Andrew Hunt and David Thomas?


Boasting features such as built-in ad-blocking and VPN, this browser began as a research project in 1994

What is Opera?


This element was once 'all the rage' because you could put it inside a `map` element and add links to different parts of an image.

What is <area>?


Where am I? Look through the `window` and figure out this useful useful piece of information.

What is `Location`?

(Though Window.location is a read-only Location object, you can also assign a DOMString to it. This means that you can work with location as if it were a string in most cases: location = '' is a synonym of location.href = ''.)


This sometimes useful, sometimes algorithm at the core of CSSdefines how to combine property values originating from different sources.

What is the cascade?


This co-authored book's sales pitch says "Learn how to design beautiful user interfaces by yourself using specific tactics explained from a developer's point-of-view."

What is Refactoring UI?


With 38% of global market share, this operating system is number one.

What is Android?

(Windows at 35%, iOS at 14%)


The penultimate header element in descending importance.

What is <h5>?


Spawn a Web Worker to keep your interface snappy and comminicate with it by calling this method.

What is `Worker.postMessage`

(Sends a message — consisting of any JavaScript object — to the worker's inner scope.)


Location! Location! Location! There's no better place for your style rule to ensure it gets applied

What is inline as a style attribute?

(although !important is an auto-win)


Whether it's 'High Performance JavaScript' or 'Understanding ECMAScript 6' that you want to learn... grab a book by this prolific 'Human who Codes'

Who is Nicholas C. Zakas?

(creator of ESLint)


This site-specific-browser (SSB) application for macOS was built on WebKit2 and featured on many blogs for its ability to make web applications more like native desktop apps.

What is Fluid by Todd Ditchendorf?


According to a random gist (with zero due diligence performed), the shortest valid html document includes a `doctype` and this one other element.

What is <title>?

(<!doctype html><title>.</title>)


This powerful web API put the X in AJAX and helped usher in Web 2.0 and 'living documents'

What is XMLHttpRequest


With flexbox, you can center an element on the page by setting these two properties to `center`

What are `justify-content` and `align-items`?


This tome has been stacked underneath Crockford's 'Good Parts' to poke fun at both books' subject.

What is 'JavaScript: The Definitive Guide'?


This discontinued web browser specialized in providing Web 2.0 facilities and social networking integrations with MySpace, Facebook, and YouTube. rated it 5 out of 5 stars.

What is Flock?


Want to bump up the size of some text? This now-obsolete element once used to do the trick.

What is <big>?