Developed by the UK-based Raspberry Pi Foundation, the credit-card-sized PC took less than a year to reach the milestone, having gone on sale last February.
The micro computer hit several stumbling blocks on its way to market, but sold out within minutes when it arrived in specialist computing stores.
Raspberry Pi is a low-cost device that runs the Linux OS and comes uncased without keyboard or monitor, designed to boost interest in computer programming at grassroots level.
The Raspberry Pi App Store went live last month, playing host to free and premium applications for the machine.
Raspberry Pi is now available to purchase for less than £22.
