How does Adblock work?

I know that extension is the work of the devil and looses many a website over 40% of its ad revenue, but how does it work? How does it identify advertisements and stop you from seeing them?

Answers appreciated,

    ~pipnina

It uses blacklists. It simply prevents the browser from downloading page elements that match the rules specified in blocking lists.

You can read those lists yourself:

https://easylist-downloads.adblockplus.org/easylist.txt

Also, adblock is not evil. The reason it was made in the first place is because ad companies sold their soul to the devil and made the internet barely usable with their ads. Now they cry crocodile tears because 'evil' adblock users don't want to put up with their bullshit.

Wow, that's a long .txt file.

So, did this person go through half the websites on the internet, make a web extansion and a website to distribute it. Just so he wouldn't have to see adverts?

Sounds like he has a problem.

Erm, no. Firstly, there are several different adblock extensions, some for different browsers, each written by different person or several people.

Then, this is just one of the lists. There are different lists for different purposes (there lists that block tracking, malware or social buttons) and different segments of the internet. And all those lists are maintaned by different people.

So no, it's not just one guy, ad blocking is made possible by efforts of a lot of people. I have no idea how they collect rules for blocking lists, but I'm fairly sure it's not one guy going through half of the internet.

Even if it's a large collective effort and a program made to determine what are adverts; it still seems like a LOT of effort just so you don't have to see ads infront of a YouTube video.

I can only assume what they're doing is actually very simple.

 

It's not a lot of effort, compared to benefits it brings to users. You can get a better idea of how it's made here:

https://adblockplus.org/en/contribute

You can also read source code if you want.

I don't use adblock, but I use hosts file blocking. IMO works better than adblock as your browser doesn't detect it.

Necro