Often times, we would like to use videos to visually convey a thought or process. It might be easier to explain what you want to say using video footage, but embedding videos on your web page can seem like a difficult thing to do. On a Drupal site, it is actually quite simple.
The important thing to know is that Drupal makes it very simple as long as the video resides on an online video site, such as YouTube or Vimeo. Putting video files directly into the Drupal system will result in inconsistent results, depending on the users' software. Using YouTube or Vimeo, avoids those inconsistencies by providing an embed code for your video that can be placed directly into the code for your web page. The embed code will allow you to utilize the video site's player software to display the video, so everyone gets to see the video in the exact same format.