Roboto

Roboto is a sans-serif font. It goes well with Roboto Slab, Open Sans, Lato, Playfair Display, Montserrat, Futura PT, Encode Sans, Roboto Mono, Abel and Oswald. If you're thinking about using Roboto then try Give 21px a shot for content.

People commonly tag it as design, agency, portfolio, writing, tech, marketing, development, news, clean and business. You can get it from Font Squirrel, Google Web Fonts and Typekit.