Is cryptex a file?

Could you clarify for me if cryptex is indeed a file? I've encountered this term in discussions about cryptography and data security, but the exact nature of a cryptex remains unclear to me. Is it a type of encrypted file? Or is it a more abstract concept referring to a method of encryption? I'm seeking a precise understanding of what a cryptex represents in the world of cryptography and finance. Could you elaborate on this, perhaps providing a brief definition and an explanation of its role and significance in data security?