Description
The Encyclopædia Britannica has been published continuously since 1768, appearing in fifteen official editions. Several editions have been amended with multi-volume "supplements", consisted of previous editions with added supplements or gone drastic re-organizations (15th). In recent years, digital versions of the Britannica have been developed, both online and on optical media. Since the early 1930s, the Britannica has developed several "spin-off" products to leverage its reputation as a reliable reference work and educational tool.