A Pi-Hole is a DNS server that will block Advertisements. Whjn you are on the internet and you are wanting to go to a website like google.com, your computer doesn’t know where that site is. So it asks fore the Address from a DNS server. That DNS responds with the Address and your computer goes to the site because it now has the Cyber-GPS coordinates for where it is going.
A Pi-Hole has a blacklist of Advertisements, and tracking websites, and will act as the Middle-man. Your computer will ask it for the address and if it has it in its Blacklist, then it will give a bogus response, and forward all valid sites to the Real DNS server you have configured.
This means that your computer never gets the Ads so it can show them to you. It also will cache DNS entries for some time and can speed up the response to your computer.
Pi-Holes were designed to run on a tiny computer called a Raspberry-Pi, but you are able to install the software on many other things. I have it running on my Plex Server and it is so light weight that it doesnt matter.
Once you setup the Pi-Hole Software then you tell your router to point to it for DNS queries and you can tweak it from there or just leave it. Everything that is gets an Address automatically from your Router should start using the Pi-Hole for DNS. You can login and see the Queries pretty close to realtime.
It can block Ads from all over the internet including many from Youtube and Mobile Apps. You should try it out today.