What is an injective transformation?

Could you please explain, in layman's terms, what an injective transformation actually is? I've heard it mentioned in cryptography discussions, but the definitions I've found are quite technical and hard to grasp. Could you break it down for me? Is it related to one-to-one mappings? And how does it fit into the larger context of cryptography and finance? Would understanding injective transformations help me better comprehend complex financial transactions or cryptocurrency mechanisms? I'm really curious to know more about this concept and its practical applications.