uBlock Origin is a free and open-source, cross-platform browser extension for content-filtering, including ad-blocking. The extension is available for several browsers: Safari, Chrome, Chromium, Edge, Firefox, and Opera. uBlock Origin has received praise from technology websites, and is reported to be much less memory-intensive than other extensions with similar functionality. uBlock Origin's stated purpose is to give users the means to enforce their own (content-filtering) choices. As of 2018, uBlock Origin continues to be actively developed and maintained by founder and lead developer Raymond Hill.
Find out more about the tool over at Wikipedia here.