WordPress offers a huge space for creativity and flexibility when designing and developing new websites. Any type of website can be built on top of it: from blogs to newspapers, corporate websites to landing pages and even social networks. All you need is a theme coded to handle that functionality.To simplify developing new themes, there are awesome WordPress theme frameworks and starter themes that you can use as a base for skipping the repetitive steps and begin with an optimized playground.

Skelton

It is a theme aimed at helping you build simple, uncluttered, useable, and mobile-friendly websites. Skeleton has styling for typography and form elements + includes simple tabs and accordions. The theme is based on and inspired from Skeleton Responsive Boilerplate, Theme Options Framework, Thematic Framework, Formalize and TwentyTen Theme.

Bones

Bones is a theme following the mobile first approach that has a detailed + organized CSS, in-depth documentation with tutorials and details on every level. Many useful features exist including page navi, breadcrumbs, related posts and HTML5 video with fallback.

Gantry

Detailed admin interface with 65 base widget positions and 38 layout combinations that provide a huge space for customization. There are lots of built-in features including the CSS and JS compression, speed-optimized codebase, several widgets and gizmos such as font-sizer, Google Analytics, to-top smooth slider, IE6 warning message, etc.

Starkers

Completely naked  WordPress theme built to be a starting point for theme designers. It’s a stripped-back version of the ‘Twenty Ten’ theme that is bundled with each WordPress download. The theme is based on YUI Reset and it is totally unstyled.

Wonderflux

Solid, easy to update and flexible platform you can use for any WordPress project. It has location-aware template parts that allow you to concentrate on the content, not the code. The framework comes with a fully dynamic CSS grid system, simple administration controls and over 100 display hooks.

Reverie

A HTML5 WordPress framework based on ZURB’s Foundation and HTML5 Boilerplate. It can almost be used out-of-the-box. There are 2 widget areas; sidebar and footer and 2 menus (top navigation menu and footer information menu). Also works with bbPress 2.0.

Costellation Theme

The Constellation theme is a great base for any WordPress-powered website. It has the styles for creating responsive pages, has a HTML5 code and comes with a flexible grid system. The theme is based on the HTML5 Boilerplate.

Flexible

Flexible is a carefully-coded child theme of the default Twenty Ten theme and built-with any browser size in mind. It has a Facebook FanGate integration and packed with Themekit (which is a plugin for plain simple customization via WordPress editor).