Glossary
SSL certificate
An SSL certificate (more accurately TLS certificate) is the cryptographic credential that lets a website serve traffic over HTTPS instead of unencrypted HTTP.
SSL/TLS certificates encrypt traffic between the browser and the server, protecting data in transit. Browsers display the padlock icon next to the URL when a valid certificate is in use.
Modern certificates are typically issued for free by Let's Encrypt or ZeroSSL and auto-renewed every 90 days. Most managed hosting platforms (Vercel, Netlify, Website Killer) handle issuance and renewal automatically.
Sites without HTTPS are flagged 'Not Secure' by Chrome, Firefox, and Safari — and Google ranks HTTPS sites higher than HTTP equivalents.
Example
Pointing your custom domain at Website Killer's nameservers triggers automatic SSL issuance via Let's Encrypt; the padlock appears within minutes.