Cookie
In plain terms
A small piece of data a site stores in the browser.
Going deeper
A cookie holds data the browser sends back to the server on each request, used for sessions, preferences, and tracking. It remembers state across requests.
Under the hood
Attributes like HttpOnly, Secure, and SameSite control security; central to sessions and privacy debates.
Examples
Sessions, login state, preferences, tracking, SameSite, HttpOnly.
Think of it like...
Like a coat-check ticket the site gives you to recognize you on return.