Good day everyone..
I took this timeout to share this knowledge with you guys. 
This tutorial is based on how you can convert and download any video on YOUTUBE to any format of your choice, also any type of audio format and download as mp3.
You don't need any application.
Conversion and downloading are very fast.

HOW TO DOWNLOAD 
1. Goto.. www.youtube.com 
2. Search for the video you want to download & click  on it.
3. Copy the  URL address, e.g.  
https://www.youtube.com/watch?v=uPL6Cn-WI5o..
   to your clipboard.

4. Open another tab on your browser and enter www.convert2mp3.net.
5. On the homepage by the "right top corner" you'll see DE/EN click on "EN" to change the site write up to English.
6. Insert (paste) the video link you copied in the box below.

NOTE
If you want the video as audio (mp3) leave the box below the link but if it's video you prefer click on the "mp3" to change it to the video format of your choice.

7. Click on "convert" and wait for a minute then "download".

It's a pleasure sharing this with you guys. 
I bet you will love it, give it a try...