article_snippet: A type of fastener characterised by a helical ridge, but just what is it exactly?
article_snippet: This image featuring a series of prisms is majestic, but can you guess what This image featuring a series of prisms is?
article_snippet: The frames of the prisms in this image appear stable, but we assure you The frames of the prisms in this image are much more supple than The frames of the prisms in this image look.