The exact contents required will depend on the applicable laws or policies. Also, the definition of what constitutes “personal information” varies, but it often includes names and email addresses, and sometimes IP addresses and browser cookies.
In the information age, data is the new currency. Private information on individuals is very valuable to advertisers, businesses, and governments.
Today, many countries consider privacy to be a fundamental human right and have passed legislation to protect individuals from their information being collected and used without their knowledge. Data privacy laws usually require that anyone collecting personal information via their website needs to have a statement on how and why they do so.