Question

What is the difference between safe and secure?

Answer 1

In this particular context, "safe" is the broader of the two terms you suggest. "Safe" implies an overall consumer experience that protects the customer from all of the hazards of online buying, such as misrepresentation, unfair return and exchange policies, hidden costs, failure to deliver as promised, etc. It would also include protections for the customer's privacy which would include protection of personal financial data.
 
"Secure" on the other hand is a little narrower and is about the site itself, and its underlying IT and business practices. "Secure" implies that the site is protected against hackers and other attacks, and that the right procedures and technology are in place to prevent unauthorized access to and use of customer data.

Answer 2

security is the certainty of being safe .if something is secure it will always be safe. on the other hand everything which is safe is not secure .they can be used interchangeably to debate safety