Locksmith Coogee Enquiry - What is deadbolt and deadlatch

A customer searched Locksmith Coogee and found my site and enquired-

What is the difference between a deadbolt and a deadlatch?

A deadlatch (top picture) is a lock that will automatically lock as you close the door. A Deadbolt (bottom picture) will not lock automatically and when leaving the key must be turned to throw the bolt.

Deadbolts are illegal on apartment door as they are a fire risk.