helloliquid

Useful command line tool for converting multimedia files between formats.

Ceaser by Matthew Lein.

Need to get to grips with the CSS flex box model? See A Complete Guide to Flexbox over at CSS-Tricks.

CSS-only custom-styled selects: http://jsbin.com/yaruh

When code doesn't work cross-browser, as a last resort here's a list of browser specific JavaScript and CSS hacks: http://browserhacks.com

A source of regularly used input patterns: http://html5pattern.com

A great online tool for generating shortcut icons for the web and devices.

Because the JavaScript Date type is horribly broken, there's a date library called Moment.js with timezone support.

A responsive image polyfill. Version 2 enables the use of the HTML5 picture element.

scottjehl.github.io/picturefill

A jQuery plugin for fluid width video embeds.

fitvidsjs.com

See Chris Coyier's excellent Retina Display Media Query snippet.

Browsers have different default element styles. Several CSS resets are available, including normalize.css. Twitter's Bootstrap framework includes normalize.css.

Responsive web design is a web design approach aimed at building sites that display and function well on a wide range of devices, from mobile phones to tablets to desktops. Sites designed with RWD adapts, or responds, to the display environment using flexible grids, flexible images and CSS3 media queries.

Progressive enhancement is a web development approach starting with basic functionality for all browsers and then building more advanced functionality for modern browsers, and so improving the richness of the user experience.