HTTPS

HTTPS (HTTP Secure) is HTTP sent over an encrypted TLS connection. It protects the data exchanged between a browser and a website from being read or changed in transit, and the site's TLS certificate proves the browser is talking to the real domain.

Browsers show HTTPS sites with a padlock and warn about plain HTTP pages, especially forms. HTTPS is required for features such as service workers and HTTP/2 in browsers, and search engines prefer it. Free certificates from authorities such as Let's Encrypt have made HTTPS standard for all websites.