Hello all. I recently got a PS3 (i know it is pretty much too late, but not the point), and was wondering what is the difference between a master account and sub account. Thanks in advance.
Welcome to the PlayStation Community.
A Master Account has access to everything on the PS3 whereas a Sub Account is generally used for minors so that parents can control the content.
Also it's not too late, enjoy your PS3.
You can never convert a Sub-Account to a Master Account either.... even if they just had their 18th birthday... which I think was something Sony overlooked. It sucks, cause it forces people to either lie about their birthdate or make a new PSN ID.