Question: What html tags are allowed by wordpress.com?
Following HTML Tags are allowed in wordpress.com
address, a, abbr, acronym, area, article, aside, b, big, blockquote, br, caption, cite, class, code, col, del, details, dd, div, dl, dt, em, figure, figcaption, footer, font, h1, h2, h3, h4, h5, h6, header, hgroup, hr, i, img, ins, kbd, li, map, ol, p, pre, q, s, section, small, span, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, var
No, You can add.
script Tags are not allowed.
Question: How to embed youtube video?
Just add following code in post.
Question: Give list of URL which videos is allowed by wordpress.com?
YouTube Vimeo DailyMotion blip.tv Flickr (both videos and images) Viddler Hulu Qik Revision3 Scribd Photobucket PollDaddy Google Video WordPress.tv (only VideoPress-type videos for the time being) SmugMug (WordPress 3.0+) FunnyOrDie.com (WordPress 3.0+)