Here’s a video to show you how to deadlift safely (and even bend down to pick things up safely too).
Dr. Joseph Damiani of Skyline Physical Therapy in Wyckoff (www.skylinept.com) does an excellent job of showing what goes on with the spine during bending with visuals of the spine and hip.
He even shows you how improper bending can potentially cause a herniated disc with a great visual.