Microsoft discontinued Encarta in 2009, and clients can no longer access the program. Encarta was originally a CD-ROM product distributed in the 1990s; it later turned into a free subscription that members could access online.

Microsoft Encarta used information from encyclopedias that included professionally investigated information. The program lasted until Oct. 31, 2009 when it was discontinued due to growth in the use of free encyclopedia websites such as Wikipedia. More than 2 million subscribers used Wikipedia's community-edited content in comparison to the 42,000 subscribers to Microsoft Encarta. As of 2015, Wikipedia is the seventh most-used website in the world.