Marc Andreessen | Netscape

image credit: Joi/FlickrMarc Andreessen was born on July 9, 1971 in Cedar Falls, Iowa. Andreessen is best known for being the co-author of Mosaic, the first widely-used web browser, and founder of Netscape. He is also co-founder of Ning, a social-networking site,  and is an investor in a number of Web 2.0 start-ups.