Browsers are the programs you run in order to access the web. You usually will only have one installed on your computer (unless you're on Windows, good luck deleting Edge), and it will most likely be either Chrome or Firefox. Browsers are actually very complex pieces of software that do a lot of things, but you don't need to understand them all in order to get use out of this article. There are a couple of things you need to know about browsers, though. First of all, they are goldmines for people trying to harvest your data. Browsers contain a lot of information about you, a small list of which is:
It should come as no surprise that many browsers collect this data, and sell it (try reading Chrome or Firefox's privacy policy). Another thing to take into account is the fact that the websites you visit track you as well, and most browsers do little to mitigate this kind of tracking. This puts you in between a rock and hard place, your browser yourself is harvesting your data, and then the websites you go to are as well. So what are you supposed to do?
And the answer is, use a browser that doesn't harvest your data, and that also protects you from websites trying to collect it. There are several open source browsers that fit these criteria, and the rest of this page will be dedicated to me listing the ones I have found to be the best.
Tor Browser is the single most secure browser in the world. There is no arguing that point. Tor is a bit more complicated than the other items on this list, however, because it is actually two things. Tor stands for "The Onion Routing Project", and it is a protocol that is designed to make it next to impossible for your IP adress to be traced back to you. It does this through a process called onion routing, which I will not be going in depth into here. The second part of it is the browser part. Tor Browser is really just a version of Firefox that has had a lot of work put into to make it so that it doesn't track its users, and that websites can't track its users. What makes Tor really cool, however, is that it onion routes all of your traffic. This results in a browser that doesn't spy on you, that prevents websites from spying on you, and that also makes it nearly impossible to trace your online activities back to you (granted you use it correctly).
All this being said, I wouldn't reccommend Tor for regular browsing. The goal of Tor isn't to be a day-to-day browser which you use for regular purposes, it is more intended for extraneous circumstances in which it is vitally needed for you to be as close to anonomous as possible. It is heavilly used by journalists reporting on things that they could get imprisoned or killed over, by people living in oppressive countries who might try to censor the informaiton they can access, and many others who need to stay as hidden as possible. This isn't to say that not everyone can use Tor, you should absolutely use Tor, but using it for everyday browsing isn't something I would recommend for several reasons. First of all, most websites you try to visit won't work. Tor's security mechanisms break most websites, so most places you try to visit will be unusable. It will also be incredibly slow because of how onion routing works. However, even though Tor isn't something you are likely to use on an everyday basis (nor should you, except under extreme circumstances), it is something you should keep in mind.
LibreWolf is a very good choive as far as private browsers are concerned. It is based on Firefox, but removes all of the components that collected data on users, and added some extra features to make it more resillient against tracking from websites. It has the same layout as Firefox, and using it is not that different either, so it won't be a jarring change for users of the flaming-canine. It also scores very well on <privacytests.org>, and it also does a pretty good job at blocking trackers and advertisments on Cover Your Tracks with default configurations, likely due to its inclusion of uBlock Origin by default. That being said, it is not the most private browser, even though it doesn't spy on you at all. Some trackers are able to follow it, and it is not completely fingerprint proof. Also, LibreWolf's resist fingerprinting may break some websites, but it can be turned off at the cost of reduced privacy. Despite that, I would still absolutely recommend LibreWolf, it is without a doubt one of the best browsers you can easily use for day-to-day browsing without sacrificing privacy.
Ungoogled Chromium is Chromium with all of the Google components stripped out of it. Chromium is the browser that Google Chrome is based on. Even though Chromium is open source, it still contains a lot of connections to Google, which is not good for privacy. Ungoogled Chromium removed all of the connections to Google in Chromium, as well as diagnostic and reporting information. As a result, it is a pretty good browser. It won't spy on you, but it doesn't have very good protection against websites tracking you. This can be mitigated in a few ways, which will be covered in an article I am working on and that will be released soon, but it is not very good at stopping websites tracking. If you are coming from using Chrome and want to start getting more private, Ungoogled Chromium could be a good option, but I would recommend libreWolf more.