Publicly available details–from LinkedIn, Facebook, Google, etc–are pulled together and posted online to “out” or doxx someone, with the purpose of exposing or harassing the person.
For example, as marches and countermarches became violent in Charlottesville, Twitter user @YesYoureRacist for help identifying “Nazis marching in Charlottesville.” Within minutes, names, addresses, employment locations and more were made public.
One man walking with a crowd of tiki-torch marchers was identified as a cook at a hot dog restaurant in Berkeley, California.
Hours later, the restaurant had posted signs in its windows and let The Washington Post know: the man was no longer cooking their ‘dogs.
Another man at the rally wore an “Arkansas Engineering” shirt. Doxxers found a photo of a professor at the University that looked similar. Soon, people he’d never met demanded the professor’s job. He was accused of racism. His home address was posted.
He was nowhere near Charlottesville at the time of the rally.
A few recent examples:
Newsweek writer Leah McGrath Goodman claimed to have the identity of the anonymous creator of Bitcoin.
Fox Business news anchor Lou Dobbs revealed the address and phone number of a woman who accused Donald Trump of inappropriate sexual advances.
Politico editor Michael Hirsh resigned after publishing the home address of white nationalist Richard Spencer on Facebook.
The Presidential Advisory Commission on Election Integrity
Established by Donald Trump to investigate voter fraud, published a 112 pages of email comments that criticized the Commission. Included was personal information, including names, email addresses, phone numbers and home addresses.
“Anonymous” posted the identities of Ku Klux Klan members.