A few years ago I discussed Adblock Plus. At the time this was a great tool, but it has become somewhat bloated and will now allow advertisers to bypass its filters if they pay Adblock Plus.
The replacement is uBlock Origin. It does the same ad blocking (right down to using the same curated lists of what to block) as Adblock Plus but is much more lightweight. You can read a lot more how it is quicker and less of a memory hog, as well as all the ins and outs of using it at their wiki.