DeTi stands for Decentralized Ticketing and removes the middleman from ticketing situations, giving control of issuing tickets for events back to the artists or organizers.
In DeTi tickets are issued as NFTs, thus reducing the ability for ticketing fraud. The issuer can also set a royalty percentage for resale, allowing the artists to realize gains from the secondary market, where tickets are often sold at highly inflated prices without any of those monetary gains flowing back to the artist.