Skype launched in 2003 and became one of the most widely used platforms for free video and voice calls over the internet during the 2000s and 2010s. Its incoming call ringtone became a shared sound for a generation of users who worked, studied, and kept in touch online. Microsoft acquired Skype in 2011, and versions from that era, including the 2015 call sound, circulated widely in videos and memes. The ringtone remains in use today as a nostalgic shorthand for an incoming online call.