SourceSansPro ExtraLight is a Thin Sans font which has tidy letter and Smooth finishes. This font is perfect for Formal looking design projects.
Google Font is an extensive collection of free and open-source fonts. This means that you are free to share your favorites with friends and colleagues. You can even customize them for your own use, or collaborate with the original designer to improve them. And you can use them in every way you want, privately or commercially — in print, on your computer, or on your websites.