It’s a complete list of the short-codes for video and audio files we can use on WP.
For photos, when you’re writing a new post, upload them to your account using the Upload/Insert Media button just above the toolbar (looks like a camera).
Choose where you want to add the media from, wait… then scroll down, press the “Insert Into Post” button. The photo should appear in your post. After that you choose the alignment, if you want a thumbnail with a link to the larger image, and all that stuff.