TLS (Transport Layer Security) and HTTPS (Hypertext Transfer Protocol Secure) aren’t precisely direct opposites—they’re related but serve different roles. TLS is a cryptographic protocol that provides encryption, while HTTPS is an application of that encryption to secure web communication. Let’s break it down.

TLS is the successor to SSL (Secure Sockets Layer) and works at the transport layer of the internet’s protocol stack. It encrypts data between two systems—like a web browser and a server—to ensure privacy, integrity, and authentication. It is versatile and can secure all connections, not just web traffic: email (SMTP, IMAP), file transfers (like with Connect: Direct), or VPNs. TLS operates independently of the application, handling the heavy lifting of encryption through mechanisms like symmetric-key encryption (e.g., AES) for speed and asymmetric encryption (e.g., RSA) for secure key exchange. It evolved through versions—TLS 1.0, 1.1, 1.2, and now 1.3—each tightening security and performance.

HTTPS, however, is specifically HTTP (the protocol for web pages) running over TLS (or sometimes still SSL, though that’s outdated). When you see “https://” in a URL, it encrypts the web traffic between your browser and the site’s server. HTTPS is just one use case of TLS tailored to web browsing. t relies on TLS to establish a secure session—starting with a handshake where the server presents a certificate (verified by a trusted authority like Let’s Encrypt or DigiCert), and both sides agree on encryption keys. Once set, the HTTP data (like webpage content) flows encrypted.

So, the key difference? TLS is the underlying technology—a general-purpose encryption protocol. HTTPS is a specific implementation of TLS applied to web traffic over HTTP. Without TLS, HTTPS wouldn’t exist as a secure protocol. Other differences come down to scope: TLS can secure non-web stuff (e.g., an FTP transfer), while HTTPS is all about us. When people say “HTTPS encryption,” they’re talking about TLS doing the work under the hood.