Source Sans Pro Font Family

Source Sans Pro is the first open source typeface family designed by Paul D. Hunt for Adobe and was developed mainly for the purpose of using it in user interfaces. Source Sans Pro is derived from the simplicity and readability of the twentieth-century American gothic typefaces. Selecting the best of these models, Paul adopted a rational design procedure by reducing glyph shapes to their essence.

There is a sister family Source Serif Pro. This font is free for personal and commercial use.