Web & APIsBeginner
Cookie
PronunciationKOOK-ee
Definition
A small piece of data that the browser stores for a site and sends back with every request, often used to keep you logged in.
Where you hear it
Login systems, privacy banners, analytics, and security reviews.
Examples
The session id is stored in a cookie.
Mark the cookie as
HttpOnlyso scripts cannot read it.
Common mistake
Storing sensitive data directly in a cookie. Store a session id and keep the data on the server.