Where do I get started? There are so many different ways you can do this, it has become mind boggling. However, I will give you the two most straight forward ways of doing so that work for Youtube and any other site that may host a video!
How do i save youtube videos on my computer
Option 1: Real Player
Go to real.com and download their basic media player. This is a tried and true piece of software that, although takes a while to download, it can offer you alot more than simply having an option to download videos off Youtube or anywhere else for that matter.
Once you have downloaded it, install it. When you restart your browser and go to any site that has videos, all you have to do is hover over the video and you should see a “Download” link at the top of the video. You click this nd it automatically saves the video to the default location
Option 2: Video download helper extension
This option is only available for Firefox
Go to Google.com and search for the term “Video download helper extension” and go to the top result. This will take you to the Mozilla extension/add on page for the tool. Click on install/Add extension and it will automatically add this to your Firefox browser.
When you restart your browser, go to any webpage that has a video, and you will see an icon of three rotating spheres that will “activate” or start rotating when there is a piece of media that is ready to download.
That is it. I would add screenshots but it really is that easy. And if you do have questions, please don’t hesitate to email us or leave a comment on this post and we will respond ASAP
Technology in the Classroom 
It is pretty easy in Safari as well. When you have viewed the video on YouTube go to Window -> Activity. Then look for the the largest file. Double click that and the video will start to download! Of course with the addition of Extensions in Safari I am sure that a video downloader (if there’s not one already) will be an option soon.