Adblock Plus (ABP) is an open-source content-filtering and ad blocking extension for Mozilla Firefox (including Firefox for mobile), Google Chrome, Internet Explorer, Opera, Safari, and Yandex Browser web browsers. In November 2012, Adblock Plus was also released as an app for Android devices. The extension allows users to prevent page elements, such as advertisements, from being downloaded and displayed. It is a fork of the original Adblock extension, developed by Michael McDonald.