Many online merchants and e-commerce sites use 3D Secure (Three-Domain Secure) as an added layer of security for online credit card transactions. However, some websites may not implement 3D Secure for various reasons, such as the cost or complexity of integration, target market preferences, or the nature of the products being sold.
Some common types of sites that may not use 3D Secure include:
1. **Small Businesses**: Smaller retailers or local


