HTML5 Boilerplate
HTML5 Boilerplate helps you build fast, robust, and adaptable web apps or sites. Kick-start your project with the combined knowledge

Once you have cloned or downloaded HTML5 Boilerplate, creating a site or app usually involves the following:
1. Set up the basic structure of the site.
2. Add some content, style, and functionality.
3. Run your site locally to see how it looks.
(Optionally run a build script to automate the optimization of your site – e.g. ant build script or node build script).
4. Deploy your site.

Twitter Bootstrap

It is a collection of CSS and HTML conventions. It uses some of the latest browser techniques to provide you with stylish typography, forms, buttons, tables, grids, navigation and everything else you need in a super tiny (only 6k with gzip) resource

Zurb Foundation
Foundation is the most advanced responsive front-end framework in the world. With Foundation you can quickly prototype and build sites or apps that work on any kind of device, with tons of included layout constructs (like a full responsive grid),

Skeleton
Skeleton is a small collection of CSS files that can help you rapidly develop sites that look beautiful at any size, be it a 17″ laptop screen or an iPhone. Skeleton is built on three core principles:

HTML KickStart
HTML KickStart is an ultra–lean set of HTML5, CSS, and jQuery (javascript) files, layouts, and elements designed to give you a headstart and save you 10′s of hours on your next web project.