A feature co-developed with Google (and also coming to the Pixel 8 and Pixel 8 Pro on the same day the Galaxy S24 series goes on sale), is Circle to Search. Designed to make searching for content relevant to anything you see on-screen that much easier, as its name suggests, Circle to Search works by long-pressing the home button on your Galaxy device an then simply drawing a circle around the visible content you want to know more about.
You can use your finger to draw a circle on the S24 and S24 Plus, while on the S24 Ultra you'll also be able to use the S Pen stylus.