Tiles come in different versions. For example, a tile 1/4 of the page width can take the form of a regular news item (thumbnail and headline), a journalistic post (header with avatar and author), a social media post (post content) and a post without a thumbnail (report post or article without a photo). A 1/4 tile is 300 pixels wide, so when building an index based on it, we can place the most popular 300x250px ads in it.