Photo galleries are recommended when images are the main content
of your post. When you use the photo gallery post type, the
images added to the post will automatically display in a gallery
format. The teaser will display an icon that symbolizes a photo
gallery, but visitors will only be able to see the gallery when
they click through to the full post view.
Photo galleries can also be embedded within a post so that it
appears between paragraphs of text. See
Advanced configuration settings for images to learn how to
embed photo galleries.