Skype Technologies S.A., Skype Software S.A., Skype Communications S.A., Skype Inc. and Skype Limited, are a group of companies that develop and operate the VoIP software and service Skype. Skype has its headquarters in Luxembourg City, Luxembourg. Skype was acquired by United States-based Microsoft Corporation on 13 October 2011.

Skype was released as a simple computer-to-computer, or computer-to-telephone program. Support for paid services such as SkypeOut, SkypeIn, and voice mail allows the company to generate its revenue as well as making local and international telephone calls easier to perform via the user's computer, sometimes cheaper than other companies' rates for similar services.
eBay acquired Skype Technologies S.A. in September 2005 and in April 2009 announced plans to spin it off in a 2010 IPO. It was acquired by Silver Lake Partners in 2009. On May 2011, Microsoft agreed to purchase Skype for US$8.5 billion, and announced the company is to be incorporated as a division of Microsoft called Microsoft Skype Division. Microsoft's acquisition of Skype got EU approval on 7 October 2011.

Skype faced challenges to its intellectual property and political concerns by governments wishing to control their telecommunications systems. As of 2010, Skype was available in 27 languages and has 660 million worldwide users, an average of over 100 million active each month.