The SHA-256 hashing step is where the magic happens!

SHA-256 (Secure Hash Algorithm 256) is a cryptographic hash function that takes the input PAN (Primary Account Number) and generates a fixed-size, unique hash value. This hash value is a digital fingerprint of the PAN, representing the data in a compact and secure way.

Here's what happens during SHA-256 hashing:

1. The PAN is fed into the SHA-256 algorithm.

2. The algorithm performs a series of complex mathematical operations on the PAN, involving bitwise operations, modular arithmetic, and other cryptographic techniques.

3. The output is a fixed-size, 256-bit (32-byte) hash value, representing the digital fingerprint of the PAN.

The resulting hash value has several important properties:

- *Uniqueness*: The hash value is unique to the input PAN, making it possible to identify the original data.

- *Irreversibility*: It's computationally infeasible to reverse-engineer the original PAN from the hash value.

- *Collision resistance*: It's extremely unlikely to find two different PANs with the same hash value.

By generating a SHA-256 hash value, the sensitive PAN data is transformed into a secure and compact representation, ready for tokenization!