A page in WordPress usually refers to the page post type. It is one of the default pre-defined WordPress post types. Pages are static one-off type of documents which are not tied to the blog’s reverse chronological order of content.
Is an acronym for Globally Recognized Avatar. It is the avatar system managed by WordPress.com.
A featured image is the main image used on your blog archive page and is pulled when the post or page is shared on social media. The image can be used to display in widget areas on your site or in a summary list of posts.
An avatar is an image or illustration that specifically refers to a character that represents an online user. It’s usually a square box that appears next to the user’s name.