There are lots of articles explaining personas and user profiles separately, but not many that talk about the use of both assets together to create a more insightful and comprehensive picture of the users.
To my understanding, personas is a form of archetype that is commonly used to make the connection between the user's needs and wants (hence their goals and tasks) to information that describe their various attributes. A user profile is an overview that is typically an aggregate of all the users grouped on various demographic or behavioural characteristics.
However, if you look at personas without understanding the overall user profile, it is hard to work out what the persona really represents (in terms of the overall population of users). And if you look at profiles without having a persona to relate to, it is really difficult to get a feel for what the user is like.
Is is common practice to only use one or the other, and if so why? I find them very much linked because the value of one is enhanced by the other, so I wouldn't create (and use) one without the other, yet I seldom see them referred together so I am curious to find out if there is a practical reason.