As youtube.com says “Share your videos with friends, family, and the world.” or
As vimeo.com do that “The best tools and highest quality video…”
You can publish video from link as youtube, vimeo… It’s called embed video.
Nice, professional and quick. No host better then theirs!
You also can publish video from your own host, These are usually short videos, visible at the widget area as important content of website. Often used as advertising tool, then the video start automaticly 
