Technically, this guide will still work, but it does not include any of the features and improvements that have been added.
This article will, however, still give you some insight into how the Pi-hole functions.
The Pi-hole can block ads for all devices on your network.
It was inspired as a low-cost, open source alternative to the Ad Trap.
The Pi-hole works on the the B, B+ and Pi 2 (it can also run on the Zero, but you need a micro-USB-to-Ethernet adapter) 1.6 million (if you decide to use the mahakala source list) domains known to serve advertisements can be blocked before they even reach your computer.
The list of these domains are maintained by different sites across the Internet.
The Pi-hole queries these sites and compiles them into an aggregated list, which is then stored on the Raspberry Pi to block advertisements.
Anytime a Website wants to load something from a domain on the list, it is redirected back to the Pi, so the real server is never contacted.
This can not only speed up your Web browsing, but it will also reduce your bandwidth usage because your browser is not downloading the ad from the server.
These are the steps you will take to activate your Pi-hole and begin blocking ads.
If you prefer to tinker around and do things on your own, take a look at the manual setup.
Once the installation is complete and you have configured your devices to use the Pi-hole as their DNS server, ads are instantly blocked without any configuration.