The most important tips is probably the trick to bypass the restriction on watching certain clips on YouTube due to regional copyright issues. Fortunately there is a way to bypass the regional filtering! Check out trick 6!
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As from MakeUseOf article on 10 Youtube URL Tricks:
1. Embed Higher Quality Videos
To embed high quality Youtube videos, append “&ap=%2526fmt%3D18″ or “&ap=%2526fmt%3D22″ to the embed url where (fmt 18 = stereo, 480x270 resolution, fmt 22 = stereo, 1280x720 resolution)
2. Cut the chase and link to the interesting part
To link a Youtube video to the exciting part when action starts at XX mins and YY secs, you need to add #t=XXmYYs to the end of the URL.
3. Hide the search box
To hide the search box which appears when your mouse hovers over the embedded video, add "&showsearch=0" to the embed url.
4. Embed only a part of Video
If you want to skip the first YY secs of a Youtube video, you can just append &start=YY. For example, to skip first 10 secs of a clip, add &start=10 to the url.
5. Autoplay an embedded video
To add autoplay function to the embedded Youtube video so that it starts automatically, just append "&autoplay=1" to the embed url.
6. Bypass Youtube Regional Filtering
Due to copyright issues, Youtube detects your location from your IP Address and then determines if you have the rights to access to the video. If you are denied access to certain Youtube videos due the restriction, you can just change the url from http://www.youtube.com/watch?v=
7. Download Video
If you want to download a video from Youtube but don't want to install softwares to do it, you can just replace the URL of the video from Youtube to KickYoutube to get to kickyoutube.com. It has all the options that you can choose from to download the video.
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