Well, this tutorial is from my friend, I think it is useful for people who want to download youtube videos, if useful, please share with more friends.
IDM is a very easy-to-use online downloading program. With IDM, you are allowed to record and download videos from YouTube and other popular sites. Here are the steps to download YouTube with IDM.
Step1: Download the latest version of Internet Download Manager, then close all browsers and start the installation.
Download link: http://www.internetdownloadmanager.com/download.html
Step2: After completing the whole process of installation, open your browser including Internet Explorer, Opera, Apple Safari, Google Chrome, Mozilla Firefox, etc. Then there will pop up a message “IDM Integration add-on or extension is ready to activate”. If you do not see this information, then restart the computer and try again.
Step3: Accessing to any one YouTube video, you will find a "Download This Video" button near the video.
Step4: Click the button, you can select the resolution and format of video in the drop-down list. But these options are limited to the page video, that is to say, if the maximum resolution of the video is 480P, then you cannot download a higher resolution than 480P.
Step5: Choose your download directory, and click the button to download YouTube video with IDM.
Source from http://www.videoconverterfactory.com/tips/download-youtube-with-idm.html
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