What are text files used to track a WWW user called?

The correct choice is cookies, as they are small text files created by websites that store information about a user's visit. Cookies allow websites to remember user preferences, login details, and other personalized data, which enhances the user experience during subsequent visits. They play a crucial role in tracking user interactions with a website without requiring the user to re-enter information each time they return.

Cookies are widely used in web applications to maintain session state and can also be utilized for tracking user behavior for analytics and marketing purposes. Understanding the function of cookies is essential for comprehending how web tracking and personalization work on the internet. This makes them distinct from other options listed, as they specifically relate to user information and behavior tracking on the web.