How to automatically send an email to a contact when a contact is created or updated?

How to automatically send an email to a contact when a contact is created or updated?

Hello,
After searching for 2 hours and not finding a clear, straight answer, I thought I would ask : How do I start a workflow that sends an email when a contact is create or a certain field is updated?

I can't seem to find a solution that does something so simple.

Please let me know.
Thank you!

Aurélien