Which piece of personal information do websites often require users to enter?

eye color
name
password
location

The most common type of information that a website will ask you for is a password, which is unique to that site.

Eye color is irrelevant for sites since there are only about 5 possible colors for human eyes. Most of the time there is no practical use for that information.

Location is mostly irrelevant since your location can change when you visit a site. If it is asking you for it, it's mostly for a special feature unique to that site.

Name is a close answer, but not all websites will ask you for your actual name. Instead, they will ask you for a custum username instead which is different.

the most recent one

explanation:

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