Choosing the right filterlist
As previously described, Adblock Plus requires filterlists to block ads. By itself, Adblock Plus can only see the webpage you are loading, but has to be "told" by the filterlist which elements to block. When you install Adblock Plus for the first time, it will automatically suggest a filterlist to you based on the language settings of your browser.
There are a two basic lists out there, EasyList and Fanboy's List. These two lists block the ads from the most popular (often English) websites. However, these lists do not block ads on less popular national websites. In the case that you, for example, come from Germany, you will have to subscribe to the national German filter list. In this case, this will be "EasyList Germany + EasyList". An overview of all the lists can be found
here.
It is important to note that you should not add too many filterlists to Adblock Plus. This will slow down the adblocker, therefore, your browsing. As a rule of thumb, it is highly recommended to not use overlapping filterlists (e.g. choose either EasyList OR Fanboy's List).
You can also use filterlists to protect yourself against tracking, malware, social media tracking, etc. Read more about this
here.