In Internet Information Services Manager, you're given the option between the Personal and the Web Hosting certificate store when creating or importing a certificate.
What's the difference?
from IIS.NET:
The key difference between Web Hosting store and Personal store is that Web Hosting store is designed to scale to higher numbers of certificates.
For lightweight scenarios (when you have less than 20-30 certificates) you can use any, Personal or WebHosting store.
When you have 30+ different certificates, you should use Web Hosting store for performance reasons.