Twitter Bootstrap
Examples
A responsive web framework. Responsive means, displays well on multiple platforms. The interface adjusts for usability and appearance on the desktop, laptop, tablet, cellphone.
Consists of CSS and JavaScript
Requires JQuery for some advanced components.
basics
12 column grid
tables
forms
dropdowns, button groups, tool bars, nesting
nav
navbar
References
HTML5 Frameworks
Best Frameworks for Web Design
Media Queries