I'll try to explain here,for the benefit of any others who are curious.Here's the link in your Signature:
http://americanfreedomunion.com/
Note the protocol being used - HTTP.So when someone clicks on that link,first his PC performs a DNS lookup on his ISP's DNS server(think of it as a phonebook),which redirects that request to the server(which is identified by its IP address) where the site is hosted.
After this,the page loads in the browser of the user,a process during which all the elements like text,images are transmitted in plaintext form from the host server to the user's device.The problem here is that exactly what is being transmitted can be read and stored by all intermediates in between like many datacenters and the users ISP,and of course the datacenter where the Host server itself is located.
So if I went to read the story titled "
‘Global Warming’ Cult Leader Al Gore: ‘Bitter Cold’ is ‘Exactly What We Should Expect From the Climate Crisis’",everyone upstream of my connection can see that I am doing so,if they intend do with little effort.This is dangerous because they can even see which username is mine when I log in and even passwords can be analyzed similarly,plus its obviously unsafe on public networks.
On the other hand,a HTTPS connection encrypts all the data between the host server and the user device,and all the intermediaries mentioned above will only be able to see that I visited American Freedom Union(because of the DNS request) and that so many MBs of data were transmitted.They have no clue if the data "downloaded" was a page load or an actual download(of say,a PDF) etc. as they cannot read it because encryption is foolproof.Most important they have clue which page I read etc. and my username,password is out of their reach.Even The only entity with any chance to collect user data in this scenario would be the datacenter,where the host server is located.
Take youtube as an example.If I could use it without HTTPS,my ISP,a myriad of datacenters could see that I listened to black metal videos,with the exact details of which obscure MVs I watched.They would also know that I comment "The Goyim Know" under quite a few videos.They would know my username,and if the webmaster is lousy,my password too.But as youtube transfers all data over HTTPS,all they can now see is that I visited the site,spent so much time on it and that X MB of data was transferred from their server to mine.
Hence its always a good practice to use HTTPS when possible.Coming to "Lets Encrypt",its a free,open-source SSL authority.SSL is the "certificate",the thing you need to apply the HTTPS protocol to your site.Its really easy to do,and should be a minute's work for a seasoned web admin,and maybe 5 minutes work for a newbie,thanks to some well-written idiot-proof guides out there.
Hope I did a good job of explaining things.