The Bugatti Veyron is considered the world's ultimate supercar due to its incredible speed, advanced technology, and elegant design that balances high performance. It has a top speed of over 400 km/h and can accelerate from 0-60 mph in under 3 seconds. Its 1,001 horsepower engine and lightweight carbon fiber construction allow it to achieve unprecedented speeds. While the Pagani Zonda is also a high-performance luxury car, it cannot match the world-record breaking speeds and acceleration of the Bugatti Veyron.