A few weeks ago, details of more than 33 million accounts were stolen from AshleyMadison.com, a popular website which offers users a chance to have an affair. The group of hackers, who call themselves, The Impact Team, allegedly said, they did so to highlight how AshleyMadison.com was retaining data of its customers, after charging them $19 for the same.

But it's not the only company. There are millions of them operating as free/paid services, building profiles on their users. Whether it's via a browser (Google Chrome, Mozilla or Microsoft Edge), search engines like Google.com, Bing.com, Ask.com, etc, or simply shopping apps such as Flipkart, Amazon or Snapdeal, etc, that come pre-installed on your phone — a majority of online services are building a profile on you. So, how do users safeguard their privacy? While it's not possible to keep them out completely, users can at least restrict the collection of such data. Here's a checklist: