What is the difference between Blu-ray disc and DVD?

Capacity
Blu-ray holds 25GB on a single-layer disc or 50GB on a dual-layered disc (5x that of DVD). There is also support for multi-layer discs,
which should allow for storage capacity to be increased in the future by adding more layers to discs.

Picture Quality
Blu-ray delivers content in full high definition resolution (1920x1080p) – 6x the picture resolution of DVD.

Sound Quality
Blu-ray offers the best audio possible with up to 7.1 channels of surround sound
(equal to or sometimes better than the sound heard in theaters).

Interactivity
Blu-ray utilizes Java-based menu software. This allows for improved interactive features such as seamless menu navigation,
exciting new bonus features and network connectivity (BD-Live).

Durability
Blu-ray offers the strongest resistance to scratches and fingerprints due to a breakthrough in hard-coating technologies.

For more info visit sony pictures Blu-ray facts.