How do you embed youtube videos in a thread?

Title explains it all. Please try to respond ASAP. Thanks in advance.

With [MEDIA] (no caps) tags.

Please refer to the tutorials at the start of each sub forum as well.

[MEDI A]youtubeurl[/MEDIA] without caps and without space

Thanks for all the help, I shall look into the tutorials of each sub-forum next time before asking for help.