Latest From Boxes are usually located in the middle part of the SERP and display relevant and recent articles from one single source in a series of three blocks, as shown below. They display the title of the article, the time since publication (which is a good way to let users know how fresh the article is), and the source of the post.
Here is an example of Latest From Boxes when you google a major publication such as Forbes.
Here is an example of Latest From Boxes when you google Microsoft.