I think it's stuff the FBI, CIA and other agencies use to track what web sites people browse to detect unusual focus on suspicious web sites, and to detect relationships from among the vast array of users that could be associated with web sites of terrorist/criminal organizations.

Remember when Obama held a series of secret meetings in the White House with Microsoft and other high-tech firms? I bet this was what he wanted them to gather and feed the info to government surveillance systems.

Also, remember, all the users of gmail.com eMail are housed in Alphabet's Google system, readily available for AI analysis. Same for yahoo.com, AOL.com, etc.

For example, if a small number of users are frequenting certain suspicious web sites, they could be part of a sleeper cell, etc.

Furthermore, the government could have access to Amazon, Bass Pro Shop, Academy Sports, GunBroker.com, eBay and many other sites of sellers of various weapons, including the searches, purchases, URLs, credit cards, and addresses of the buyers, to detect possible terrorists and criminals.

What do you think?