question about images in blog posts

Hello, My question doesn't have anything to do with plugins on wpmudev, but this tab says 'anything else', so Im hoping Im able to ask a non related question. if not, just delete

I have seen blog posts where there is one main image, and a few smaller thumbnails next to it. If you click on the thumbnail, then that image becomes the large image. All of this inside of the blog post. Does anyone know of a plugin that does this? below is a snap shot I took from a site that I see it on...

http://djkasper.com/temp/multiple-photos-in-blog-post.jpg