# Payment glossary

This glossary contains general terms used in the payments industry and should help you demystify the world of payments.

## Strong Customer Authentication (SCA)

SCA is mandated in [PSD2](https://www.ecb.europa.eu/press/intro/mip-online/2018/html/1803_revisedpsd.en.html)
as a way to make online payments and online banking transactions more secure.

An authentication is considered strong if a shopper is able to provide two out of the following factors:

* Something the shopper has.
* Something the shopper knows.
* Something the shopper is.


For example, a shopper is required to supply a one-time authentication code received on their phone (something the shopper has),
and a password that only the shopper knows (something the shopper knows).