A carousel is a single post made of several swipeable cards — images, graphics or short videos — most associated with Instagram and LinkedIn but available across networks. It lets you tell a sequenced story, break down a how-to, or stack an argument slide by slide within one post.
Carousels matter because they earn attention and saves. Each swipe is dwell time, the platform can re-serve the post showing a slide the viewer has not seen, and educational or list-style carousels are among the most saved formats — a strong ranking signal. They pack more value into one unit than a single image can.
Make the first slide a hook that promises a payoff, keep one idea per slide, design for legibility on a small screen, and end with a clear call to action. Number the slides so people know there is more, and put your best insight where they will not miss it.