## Transition to Web3 - Course 2 | Blockchain Basics

🎉** **Woohoo! You created your first hash.

Hashing enables us to efficiently compare whether data is changed. Many structures in the blockchain will be built using hashing.

Now, ask yourself: 🤔 Given a hash, could a computer find out what the input is?

It’s impossible to do so. A computer would be going through 2²⁵⁶ different inputs to find the matching hash, which is a lot of calculations and there is no such computational power in the world.

Next, let’s explore what a block is.