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It's great to give back to your community by making your original videos available under a Creative Commons license!
Here's how to set the licensing for this in YouTube:
After (or while) uploading your video, look under the "Advanced Settings" tab. You'll see an option called "License and rights ownership".
By default this will be set to "Standard YouTube License", which you can change to "Creative Commons - Attribution" to allow anyone to embed or re-publish your content as long as they cite you as the original author.
What does "Standard YouTube License" mean?
Essentially, it means "All Rights Reserved". Someone wanting to embed your video legally into their site (if you have allowed embedding) should confirm that you are the actual owner of the video before sharing it, so they don't get sued by the true rights-holder. Likewise, before you embed that Michael Jackson video into your website, you should be certain that the person who posted it is allowed to, and not just a fan who may have no right to redistribute the video. (That fan could get sued by the rights hoolder, and maybe you too. Most often though, the rights-holder will just ask YouTube to remove the illegal video clip, and it will disappear.)
What is Creative Commons?
https://support.google.com/youtube/answer/2797468/
This page at YouTube covers all their Copyright definitions and terms:
https://www.youtube.com/yt/copyright/