Salesforce trigger list/map values on insert/update/delete/undelete

This table shows us when Id exists in trigger:

	insert	update	delete	undelete
before	null	Id	Id	-
after	Id	Id	Id	Id

And this one shows what values of Map/List we have on different stages of trigger work:

Execution	Method	insert	update	delete	undelete
before	trigger.new()	List	List	null	-
before	trigger.newMap()	null	Map	null	-
before	trigger.old()	null	List	List	-
before	trigger.oldMap()	null	Map	Map	-
after	trigger.new()	List	List	null	List
after	trigger.newMap()	Map	Map	null	Map
after	trigger.old()	null	List	List	null
after	trigger.oldMap()	null	Map	Map	null