Google announced that you can now insert videos from Google Drive into your Google Slides. This means that you are no longer limited to using videos that are hosted on YouTube. You can upload any video that you own into your Google Drive account then insert it into your Google Slides presentation. You can event specify the start and stop time for a video within your slides.
Applications for Education
For years one of the top complaints about Google Slides has been that you can only use videos from YouTube in your slides. That changed today. And since G Suite for Education offers students unlimited storage, there isn't a limit to the quantity or length of videos that students can add to their presentations.