NSXMLParser and NSKeyedArchiver, NSKeyedUnArchiver

I recently learned to use OC school NSKeyedArchiver, NSKeyedUnArchiver archiving, archiving this part of the solution and found that as long as its own entity classes implement two methods NSCoding protocol as an XML file can be archived, you can also read data from an XML file into their own entity classes inside, so I think they wanted to be able to use xml serialization anti-serialization this thing done.
But today the online search to parse XML, found that many people use NSXMLParser this thing from the class did not mention using NSKeyedArchiver, NSKeyedUnArchiver it, are useless do these two things?