There are tons of wordpress theme available for different categories. Among them I have selected Best 5 Free WordPress Theme 2015.
Hathor Theme makes it easy to fully customize the Layout, Colors and Style within minutes. The theme is SEO Friendly and has plenty of user-friendly options.
The Cirrus theme is a soft, user-friendly, WordPress blog theme. Perfect for your personal or business blog with a fully responsive layout based on the newest release of the Bootstrap 3 mobile-first, front-end framework.
Colorway is Simple, Elegant, Responsive and beautiful Theme with Easy Customization Options.The Customization Options includes using your own Logos, Backgrounds, Analytics and your own Custom Footer Texts and Analytics that can be tweaked using Theme Options Panel.
A minimalistic theme with horizontal scrolling.
Parallax One is a simple and elegant theme that can be used for any purpose. It comes with a clean and beautiful design, created to put content first. The theme’s classy look is enforced by a trendy parallax effect, hence the name of the theme.