work at the Bill & Melinda Gates Foundation. He gradually transferred his duties to Ray Ozzie and Craig Mundi stepped down as chairman of Microsoft in February 2014 and assumed a new post as technology adviser to suppo newly appointed CEO Satya Nadella. Since 1987, Gates has been included in the Forbes list of the world's wealthiest people. As of September he is the richest person in the world, with an estimated net worth of US$86 billion. In 2009, Gates and Warren E founded The Giving Pledge, whereby they and other billionaires pledge to give at least half of their wea philanthropy. The foundation works to save lives and improve global health, and is working with Rotary Interna to eliminate polio. 1. When was William Henry Gates born? 2. Who launched Microsoft - the world's largest PC software company? 3. Did Gates step down as chairman of Microsoft in February 2014? Who founded the Giving Pledge? 5. What's the purpose of this foundation?