Penguin

With IPv6, each address on each interface has a flag associated with the IP address, detailing how it was assigned and whether it should be used.

 Name   Meaning 
 permanent   This address was configured manually (default) 
 dynamic   Thie address was learnt through RouterAdvertisement? 
 secondary   This address is not used when selecting a source address of a new IPv6 packet. 
 primary   This address is used when selecting a source address of a new IPv6 packet. 
 tentative   This address was added to an interface, but it's not yet clear if it's unique on this network segment, so the address is not used (yet). 
 deprecated   This address has expired and will not be used for further outgoing connections (but will still be around in case of connections that are still using this address) 

Each address also has a validity time, indicating how long the address should be valid for. This is usually forever for manually assigned and LinkLocal addresses.