Viagogo is an online ticket marketplace that allows users to buy and sell tickets for various events, including concerts, sports, theater, and more. Founded in 2006, it operates globally, connecting buyers with sellers, often enabling users to purchase tickets that may be sold out elsewhere.

Key features of Viagogo include:

1. Wide Selection: Users can find tickets for a vast array of events and venues.
2. Resale Platform: It enables individuals to resell tickets they can no longer use, often at marked-up prices.
3. Buyer Protection: Viagogo offers guarantees to buyers, such as ensuring tickets are valid and delivered on time.
4. Mobile App: The platform includes a mobile app for easier access to tickets on the go.

However, Viagogo has faced criticism for high service fees, pricing transparency, and the ethics of resale pricing. Users are often advised to research and compare prices before purchasing.