If cryptography was a body, its hashing algorithm would be the heart of it. If cryptography was a car, its hashing algorithm would be its engine. If cryptography was a movie, its hashing algorithm would be the star. If cryptography was the solar system, its hashing algorithm would be the sun. Okay, that’s probably too far, but you’ve got the point, right? Before we get to the what hashing algorithm is, why it’s there, and how it works, it’s important to understand where its nuts and bolts are. Let’s start with hashing.
What Is Hashing?
Let’s try to imagine a hypothetical situation here. Suppose you want to send a message/file to someone and it is absolutely imperative that it reaches its intended recipient in the exact same format. How would you do it? One option is to send it multiple times and verify that it wasn’t tampered with. But what if the message is too long? What if the file measures in gigabytes? It would be utterly absurd, impractical, and, quite frankly, boring to verify every single letter, right? Well, that’s where hashing comes into play.