Mitchell David Kapor was the founder of Lotus Development Corporation (/organization/lotus-development-corporation) and the designer of Lotus 1-2-3, the "killer application" often credited with making the personal computer ubiquitous in the business world in the 1980s. He is known as an entrepreneur, investor, social activist, and philanthropist. Kapor has been the Chair of the [Mozilla](/organization/mozilla) Foundation since its inception in 2003. He founded the Mitchell Kapor Foundation to support his philanthropic interests in environmental health. He also co-founded, and is on the board of, the Level Playing Field Institute, a nonprofit dedicated to fairness in education and workplaces. Kapor is also Chair of the Board of Directors of [Linden Lab](/organization/secondlife), a [San Francisco-based](/maps/city/San%2520Francisco) company which created the popular virtual world [Second Life](/product/second-life), and a member of the Advisory Board for the [Wikimedia Foundation](/organization/wikimedia-foundation). In 1990 Kapor's new company On Technology introduced their new product On Location, an application designed for the Macintosh that contained an indexing system that permit quick retrieval and display of text on the Mac's hard disk. "We think we're being cagey by bringing it out on the Mac first," Kapor said. "It's a richer medium than MS-DOS, and if we have a hot product in the Mac market, it will be easier to get into the PC market." In 2001, Kapor founded the Open Source Applications Foundation, where he is now working on Chandler, a modern personal information manager built using open source tools and methods. In 2006, Kapor founded his latest startup, [Foxmarks](/organization/foxmarks), based in San Francisco.