Cookies are used to do which of the following?

Store contents of electronic shopping carts

To track web activity

Store your ID and password for subsequent logons to the site

All of these

Cookies are text files with small pieces of data such as a username and password etc.
The purpose of the computer cookie is to help the website keep track of your visits and activity.
That is used to identify your computer as you use a computer network.
Specific cookies known as HTTP cookies are used to identify specific users and improve your web browsing experience.