> ## Documentation Index
> Fetch the complete documentation index at: https://docs.mention-me.com/llms.txt
> Use this file to discover all available pages before exploring further.
# Understanding Hashed Data
> What hashed data is, how Mention Me uses it, and how it differs from encryption.
## What is hashed data?
Hashed data refers to information that has undergone a one-way transformation using a hash function. This process takes something like an email address and turns it into a unique set of characters.
### How hashing works
* **Consistency** -- The function always produces the same output for the same input. Each email address generates a distinct hash.
* **Irreversibility** -- It is impossible to reverse a hash back to the original email address.
We use "salted" hashes, combining the email address with a secret key before hashing. This makes it harder for outsiders to link hashes to emails.
## How hashed data is used on the platform
When you view the Customer section, you may find a hashed record for an email address. We store hashed records in two cases:
* When a client launches with us, we import their existing customer list.
* When someone places an order with one of our clients.
In both cases, we only use the hashed data to indicate that the person has had a relationship with the brand and, as an existing customer, cannot claim a reward. We do not use hashed data for any other purpose.
### What a hashed record looks like
## Hashing vs encryption
* **Hashing** -- A one-way process that turns data into a unique string. Irreversible. No keys involved.
* **Encryption** -- A two-way process using a key to transform data. Reversible with the correct key.
## Key takeaway
We store data in hashed form for security. The original email address cannot be recreated from its hash.