Uber was founded in 2009 in San Francisco by Travis Kalanick and Garrett Camp. It operates a mobile app and website that connects riders to drivers for transportation services like rides and delivery. Uber launched various marketing campaigns over the years, including delivery of Christmas trees and hot air balloon rides. It uses dynamic pricing and ratings for both riders and drivers. Drivers must pass requirements like submitting a selfie. While convenient, Uber faces some legal challenges in countries where it disrupts existing transportation regulations.