The Social Semiotics method is a study that looks at meaning, and how it is portrayed through communication and design, both online and in social interactions. Social Semiotics was heavily researched beginning in the early 1900's, and is important to our everyday communication. It is important because it helps us understand how communication works in society, and how there are different learned signs and symbols in different cultures. Multimodality is one method of Social Semiotics, where multiple forms of communication are considered - language, gestures, images, and more. Also, including context with communication is a key factor in understanding social cues in different cultures and situations. Placing photos on certain parts of the screen can help readers interpret text better - for example, placing photos on the left side of the screen can help people process them faster than if they are on the right.
Here is one example of image placement, a National Geographic page with a mountain lion - the image is placed on the top, with text below. We automatically look at the text below for context about this image, and we look below the image for more information about it. Opening an article with a bold photo that distracts from the rest of the page catches your attention and leads you to read on about it.
One more example of image placement is the Dune: Part Two review page on Rotten Tomatoes. When you first open the page, you see reviews for other movies and the trailer for the movie you clicked on. It takes a little bit of scrolling to find the ratings and reviews for the movie itself. On the left, and usually the first thing you see, will be links to other movies that are featuring right now. On the right, you see the trailer for the movie you clicked to review. It seems like the intention here is to keep you clicking through movie reviews, since they are the first thing you see and they are easily accessible.