SSL

SSL stands for Secure Sockets Layer: the technology that encrypts traffic between a visitor’s browser and a website. Today the protocol in use is actually TLS (Transport Layer Security), but people still say “SSL certificate” in everyday talk.

An SSL/TLS certificate proves the site is who it claims to be and enables HTTPS — the padlock in the address bar. Without it, passwords, forms, and payment data travel in ways that are easier to intercept. A biometric authentication flow is the same: the scan unlocks a credential, and SSL protects the trip. Browsers warn on insecure pages, and search engines favor secure sites.

A real-life example of SSL

Sending a postcard vs. a sealed envelope: anyone along the route can read the postcard. SSL/TLS seals the envelope so only the intended recipient can open it. For a shop checkout or a login form, that seal is non-negotiable.

Certificates often come free (Let’s Encrypt) or via your hosting / CDN provider and must be renewed or auto-renewed. For security basics that include SSL, see Web Wise: How Can I Keep My Website Secure?.