How much your data is worth - and how to stop people profiting from it

Companies generate massive profits from people's information, with experts describing user data as "the new oil".

Some of these companies are household names but many are unknown, with one analyst comparing the relationship between companies and users as "David vs Goliath".

Is there anything you can do about it, or are you resigned to having companies know all about you - and make money on it?

How companies collect data

Sam Jones, founder of Gener8 , a company that helps users make money from their own data online, told our Money team how companies farmed data on users.

"Companies collect data about people through a range of methods, many of which operate quietly in the background as we go about our daily lives," he said.

"Most of us have heard of 'cookies', but perhaps many of