Twitter is taking on Google and Facebook, today’s leaders in online video advertising, with the introduction of ads that play automatically in users’ timelines. The new function will also apply to GIFs and Vine videos. “When users scroll through their Twitter feeds and see a video, it will begin to automatically play while muted,” The Wall Street Journal explains. “Clicking on the video will play it in its entirety in the full-screen viewer with sound. Think Facebook-style video, as opposed to the model that requires a click to start playing.” Since video ads command higher rates than display ads, the auto-play feature represents a much-needed financial opportunity for Twitter.