WordPress automatically adds paragraph tags (<p>) in the posts wherever it notices double line-breaks. For example, if you write one line and press the return key twice, it considers you want to add a paragraph there, and then suitable tags will be added when you publish or preview the post.
You don’t see the tags added in the post editor, but they will show up in the markup when you view the source of your post.
The same thing happens with the WordPress image captions when your inser...