Founded in 2003 by Niklas Zennstrom and Janus Friis, Skype is a proprietary telecommunications application that offers voice and video calls, instant messaging, file transfer, and other features. It was acquired by eBay in 2005 and later by Microsoft in 2011. Initially a hybrid peer-to-peer and client-server system, Skype transitioned to a centralized service in 2012. As of March 2020, Skype had 100 million monthly users and 40 million daily users. However, during the COVID-19 pandemic, it faced competition from Zoom and experienced a decline in market share.