Tech Tuesday: Browser Cache versus Cookies

Browser Cache versus Cookies

Chances are at some point you have been told to clear your computer’s browser cache or your computer’s cookies. But what are these things, and why do they matter?

What is a Browser Cache?

When you want to find something on the internet you use a browser program such as Google Chrome, Firefox or Safari. The browser’s job is to connect to a different device, retrieve the website information and decode it onto your computer so that you can read, view, and click through the site. As you can imagine, this can take quite a bit of time.

This is where a browser cache comes in handy. When you access a website for the first time, often that website will store bits of information on your hard drive in the form of images, documents, or program language. Usually these bits are things that will stay the same on a website from visit to visit, such as headers, company logos, or interactive objects like buy buttons. This means that the next time you visit that website your browser will not have to work as hard to decode the site’s information because some of it is already stored on your computer and ready to go.

What is the Difference between a Cache and a Cookie?

Have you noticed that when you visit many websites, a banner pops up to inform you that the site uses cookies? It often asks you to accept this before continuing to the website. Although many of us click “OK,” what exactly are we agreeing to?

Cookies, like a browser cache, are bits of information stored on your computer. The difference between the two is the function. A cookie is a bit of text information that a website uses to identify your browser as a specific user. This can include anything you have added to a shopping cart, and any address or log in fields you have filled in. However, most websites simply attach an ID cookie to your computer so that they can accurately track where visitors are clicking on their sites, and how many times people return for another visit. Cookies are much smaller bits of data than a cache usually is. Some cookies are very temporary, and are deleted once you close your browser session. Others stay on your device for a longer period of time, but often have an expiration date so that they, too, get deleted after a period of time.

Are Browser Caches and Cookies Harmful?

Although both a cache and cookies often have a bad reputation, they are not harmful to the operation of your computer. They are simply pieces of text and images- they are not capable of ‘doing’ anything on your computer. They are not like a virus or a program.

Where there can sometimes be a problem with the cache is when a website changes or updates one of their files. It will not automatically change the cache on your computer. Instead, the cache will attempt to load an item that no longer fits into the rest of the website. This can cause sites to load incorrectly, or can cause buttons and links to stop working. These situations will require you to clear your cache.

Cookies, on the other hand, can potentially be a security problem. It is possible for a hacker to gain access to your cookies. This could be particularly harmful if the cookies include sensitive information such as mailing addresses, security questions, etc.

Another potential problem is with a specific type of cookie called a “tracking cookie.” These types of cookies are stored on your computer, but they can sometimes be accessed by a site other than the one that left it there. This type of cookie is most often used by advertising companies. Have you ever looked at a product, like a new shoes, only to find that suddenly many of the ads you see on other websites are directing you to buy shoes? This is due to a tracking cookie. Tracking cookies can potentially share a lot of information about your internet habits, such as browsing history, location, past purchases, and what links you have clicked.

This article includes more information about tracking cookies, instructions on how to clear them, and how to prevent them from being stored on your device:  https://privacy.net/stop-cookies-tracking/

Ultimately it is a good idea to clear your cache and cookies from time to time. This will keep your information more secure, and help your computer run more effectively. However, keep in mind that when your cookies are cleared you will need to log back in to all websites when you revisit them, so be sure you know your passwords.

This site contains instructions on how to clear your cache and cookies for different internet browser programs: https://www.liquidweb.com/kb/how-to-clear-browser-cache-and-cookies/

This site explains how to clear just the cache, if you do not want to lose your login status information in your cookies: https://kinsta.com/knowledgebase/how-to-clear-browser-cache/