Information technology

1946: The first general-purpose high-speed electronic digital computer, the ENIAC (Electronic Numerical Integrator and Computer), was demonstrated to the public by its creators, J. Presper Eckert, Jr., and John W. Mauchly. [ Discover how well you know computers and operating systems .]

2005: Steve Chen, Chad Hurley, and Jawed Karim registered YouTube, a Web site for sharing videos; it would become hugely popular, with more than one billion unique users visiting the site every month. [ Test your knowledge of tech companies .]