Knovio is a free service that allows you to easily create online presentations. It is currently in private beta, but you can request access from their main page. It is free to use and lets you turn PowerPoint slides into video presentations in your browser with no hardware or video software needed. All you need is a webcam and microphone.
Knovio is very easy to use. It takes 3 steps to create and share your presentation online. First, you create and then upload your PowerPoint presentation to the site. Then you record the video of you doing the presentation with the slides, and then you share the finished product.
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