Fifteen years ago this week, Bill Gates stood before a crowd to launch what was to be one of Microsoft’s most successful products ever, Windows 95. Their $300 million advertising campaign included lighting up the Empire State Building in Windows colors and treating Londoners to free newspapers, resulting in customers waiting in lines for hours to get a copy of the latest and greatest in personal computer operating systems.

Looking back, the Windows 95 platform seems elementary, obsolete, graphically outdated, and even ugly by today’s standards. However, at the time the operating system far surpassed its competition in technological stability and capabilities. Many features we now expect in recent versions of Windows, such as the start menu and taskbar, were introduced with the debut of Windows 95. It became the personal computing norm, with over 70% of the computer-using world operating on it just two years after its debut. » Read more: Windows 95 Celebrates its 15th Birthday