Here are built-in shortcodes and you can use «Shortcode Generator» to help create sample shortcode in page/post options box.
[youtube width="600" height="350" video_id="jQ1s-kW_RUk"]
[vimeo width="600" height="340" video_id="74013667"]
[video width="600" height="340" img_src="http://themes.themegoods.com/extremis_wp/wp-content/uploads/2010/10/shutterstock_73187281-610x350.jpg" video_src="http://video-js.zencoder.com/oceans-clip.mp4"]
