Cookies provide functions such as remembering personal configuration settings for a website, and holding contents of a shopping cart until the transaction is completed.

All About Cookies

Many cookies are tracking cookies which collect information about you, your interests, and your shopping preferences, and can log where you go on the Internet. This helps companies develop market analyses and throw up ads tailored to your interests. That is why if you are curious about, say, some disease you might see specific prescription ads showing up shortly thereafter on your computer. Many of us consider them to be a gross invasion of privacy. I regularly delete all of my cookies because of this. The only problem is that then I have to re-enter passwords for some sites because the cookie that logged me in was deleted when I purged all the cookies. Here is a discussion of these not-so-benign cookies: https://www.tomsguide.com/us/-tracking-cookie-definition,news-17506.html

All browsers typically have ways to easily clear your cookies. For example, if you click in the upper right of Chrome, the drop-down menu has a listing called: "More tools"; if you click on that, there is an option to "Clear browsing data." Some browsers can be set to automatically clear the cookies whenever you close them. If you've never done this, you probably have thousands and thousands of cookies and it may take a little while before the browser finishes clearing them.

Thanks, Kudzu. You answered my main concern - that is, if I clear all cookies, then I better be sure I can remember all the internet passwords I might need again.

mtvhike-

Not all sites work the same: I only have to re-enter passwords for some of my web sites after I clear the cookies, but that could be a function of some additional apps I have...can't say for sure. In any case, it's always a good idea to have all of your passwords written down and stored in a safe place. ;-)

Your PC will operate quicker if you clear cookies and cached pages in your browser regularly. You can set FIrefox to do this when the browser is closed, others it's a step requiring a few quick clicks. Yes, you need to re-enter passwords afterwards but that's a small inconvenience compared to the performance gain.

https://support.mozilla.org/en-US/kb/cookies-information-websites-store-on-your-computer

Elmer, at least for my web browsing, pages load much faster if they have been previously stored in the browser's cache. Easy to see this when I clear Firefox's cache & the first time I browse, say, gardenweb, the loading is much slower. The caching is done for that reason.

Majority of browsers have a setting for how much disk space is allotted for temp files ... cookies and caching pages (cookies probably take priority over page caching). Adjust the setting if there's concern for a huge cache causing slow performance.

dadoes-

That might deal with performance problems, but there's still the issue of how much snooping you want to allow on your computer. ;-)