A cookie is a small file of data that a website sends to your browser to identify you and remember information about your visit. Cookies can make your online experience easier and more personalized by:

• Recording your web usage 

• Keeping you signed in
• Remembering your preferences
• Recording what you have put in your shopping basket
• Giving you locally relevant content
• Saving login information

Cookies are stored on your device locally, which frees up storage space on the website's servers. This allows websites to personalize content while saving money on server maintenance and storage costs. 

Some cookies are necessary for security purposes, such as authentication cookies that save a user's login information. However, some sites may use cookies to store personally identifiable information, such as payment card information. If that type of information is sent unencrypted, it can be intercepted and used by a criminal.

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