Vehicle / Proof of Ownership in UK?

I bought a car in UK for first time on 20/June after few days i got V5C document , the problem on the document written ((((( This Document is Not Proof Of Ownership )))) ... very strange system her , even my name written in the document ... so who is the ownership of this car ???? is there any different between Ownership and Registered person ?? PS. i just moved to UK few months ago ,every day i hear , see , face different unusual funny things ...