Originally Posted by mccdaddy
I'm able to embed .mp4 onto my website but, strangely, if I convert an .avi or .3gp file to .mp4 (using Format Factory) it will not play with the video tag.
Which codec is used to encode your video? MP4 is just a container. If the container doesn't contain a format that your browser supports, nothing is going to play.
As far as I'm aware, the supported formats/containers are Theora (Ogg), H.264 (MP4), and VP8 (WebM).