BSCI - OSPF - LSA types

Link-state Advertisement Types are as follows:
 Type
 1 - Router LSA - Most common, used in an Area, lists a routers neighbor and it's cost
 2 - Network LSA - Generated by DR/BDR, advertises all routes with in an area - Does not cross the ABR
 3 - Summary LSA - ABR's generate these to summarise routes from a different area, sent between areas,    summarisation is manually configured.
4 - ASBR LSA - Sent FROM an ABR with the IP's of ASBR's in any OSPF areas. Routes in OSPF areas use these to locate the external network.
5 - External Link LSA - Advertises ASBR summary routes out, contains routes external to OSPF
7 - NSSA External LSA - Similar to Type5 LSA but generated by an ASBR in a Not-So-Stubby-Area, converted in to Type5 LSA's by the receiving ABR