Web World

jQuery  is purely designed to simplify and standardise scripting across browsers. It focuses on the low-level stuff: creating elements, manipulating the DOM, managing attributes, performing HTTP requests, etc. jQueryUI  is a set of user interface components & features built on top of jQuery (i.e. it needs jQuery to work): buttons, dialog boxes, sliders, tabs, more advanced animations, drag/drop functionality. jQuery and jQueryUI are both designed to be 'added' to your site (desktop or mobile) - if you want to add a particular feature, jQuery or jQueryUI might be able to help. jQuery Mobile , however, is a full framework. It's intended to be your starting point for a mobile site. It requires jQuery and makes use of features of both jQuery and jQueryUI to provide both UI components and API features for building mobile-friendly sites. You can still use as much or as little of it as you like, but jQuery Mobile  can  control the whole viewport in a mobile-frie...

What is the difference between CSS variables and preprocessor variables ? Variables are one of the major reasons CSS preprocessors exist at all. The ability to set a variable for something like a color, use that variable throughout the CSS you write, and know that it will be consistent, DRY, and easy to change is useful. You can use native CSS variables ("CSS Custom Properties") for the same reasons. But there are also some important differences that should be made clear. A simple example of preprocessor variable usage is like this: $brandColor : #F06D06 ; .main-header { color : $brandColor ; } .main-footer { background-color : $brandColor ; } The above code would do nothing in a browser. The browser wouldn't understand the declarations and toss them out. Preprocessors need to compile into CSS to be used. This code would compile to: .main-header { color : #F06D06 ; } .main-footer { background-color : #F06D06 ; } This is no...