[Atomic Glue](atomicglue.co)
WEB DEVELOPMENT
Home › Glossary › Web Development· 215 ·

HTTPS

\ˌeɪtʃ tiː tiː ˈpiː ˈɛs\abbr.
Filed underWeb DevelopmentSEOSecurity
In brief · quick answer

HTTPS (HyperText Transfer Protocol Secure) encrypts HTTP communication using TLS, protecting data integrity and privacy between client and server.

§ 1 Definition

HTTPS is the secure version of HTTP. It layers TLS (Transport Layer Security) on top of standard HTTP, encrypting all data in transit. This prevents eavesdropping, tampering, and man-in-the-middle attacks. HTTPS is not optional. Google has used HTTPS as a ranking signal since 2014. Browsers mark HTTP pages as "Not Secure." Every form submission, every login, and every API call should happen over HTTPS. The shift from HTTP to HTTPS has been one of the most important security improvements in web history. TLS certificates are now free from Let's Encrypt, and tools like Certbot automate the entire setup. There is no remaining excuse for plain HTTP.

§ 2 How it works

When a client connects to an HTTPS server, a TLS handshake occurs. The server presents its SSL/TLS certificate (containing a public key). The client verifies the certificate against a trusted Certificate Authority (CA). They negotiate a cipher suite and exchange session keys. After the handshake, all data is encrypted symmetrically for the remainder of the session.

§ 3 Beyond encryption

HTTPS also provides authentication (you know who you are talking to) and integrity (data cannot be modified in transit). It enables HTTP/2 and HTTP/3, which require encryption. It is a prerequisite for many browser APIs like service workers, geolocation, and payment requests.

§ 4 Common misconception

HTTPS does not make your website "secure" in the general sense. It only secures the transport layer. Your server can still be vulnerable to SQL injection, XSS, or authentication bypasses. HTTPS is necessary but not sufficient for security.

§ 5 Note

Mixed content occurs when an HTTPS page loads HTTP resources (images, scripts, stylesheets). Modern browsers block active mixed content (scripts), which can break your site. Always use protocol-relative URLs or explicitly use HTTPS for all resources.

§ 6 Common questions

Q. Do I need HTTPS if my site has no forms or logins?
A. Yes. HTTPS protects data integrity, prevents content injection, and is required for HTTP/2 and many browser features.
Q. Are free SSL certificates safe?
A. Yes. Let's Encrypt provides certificates with the same cryptographic strength as paid ones. The only difference is paid certificates may offer warranty or brand validation.
Key takeaways
  • HTTPS encrypts HTTP traffic with TLS, protecting against eavesdropping and tampering.
  • HTTPS is required for modern web features, HTTP/2, and SEO.
  • TLS certificates are free and automated. There is no excuse for running HTTP.
How Atomic Glue helps

Atomic Glue sets up HTTPS properly with automatic certificate renewal, HSTS headers, and secure TLS configurations. Our trust page explains how we handle security.

Get in touch
# HTTPS

HTTPS (HyperText Transfer Protocol Secure) encrypts HTTP communication using TLS, protecting data integrity and privacy between client and server.

Category: Web Development (also: SEO, Security)

Author: Atomic Glue Team

## Definition

HTTPS is the secure version of HTTP. It layers TLS (Transport Layer Security) on top of standard HTTP, encrypting all data in transit. This prevents eavesdropping, tampering, and man-in-the-middle attacks. HTTPS is not optional. Google has used HTTPS as a ranking signal since 2014. Browsers mark HTTP pages as "Not Secure." Every form submission, every login, and every API call should happen over HTTPS. The shift from HTTP to HTTPS has been one of the most important security improvements in web history. TLS certificates are now free from Let's Encrypt, and tools like Certbot automate the entire setup. There is no remaining excuse for plain HTTP.

## How it works

When a client connects to an HTTPS server, a TLS handshake occurs. The server presents its SSL/TLS certificate (containing a public key). The client verifies the certificate against a trusted Certificate Authority (CA). They negotiate a cipher suite and exchange session keys. After the handshake, all data is encrypted symmetrically for the remainder of the session.

## Beyond encryption

HTTPS also provides authentication (you know who you are talking to) and integrity (data cannot be modified in transit). It enables HTTP/2 and HTTP/3, which require encryption. It is a prerequisite for many browser APIs like service workers, geolocation, and payment requests.

## Common misconception

HTTPS does not make your website "secure" in the general sense. It only secures the transport layer. Your server can still be vulnerable to SQL injection, XSS, or authentication bypasses. HTTPS is necessary but not sufficient for security.

## Note

Mixed content occurs when an HTTPS page loads HTTP resources (images, scripts, stylesheets). Modern browsers block active mixed content (scripts), which can break your site. Always use protocol-relative URLs or explicitly use HTTPS for all resources.

## Common questions

Q: Do I need HTTPS if my site has no forms or logins?

A: Yes. HTTPS protects data integrity, prevents content injection, and is required for HTTP/2 and many browser features.

Q: Are free SSL certificates safe?

A: Yes. Let's Encrypt provides certificates with the same cryptographic strength as paid ones. The only difference is paid certificates may offer warranty or brand validation.

## Key takeaways

## Related entries


Last updated June 2026. Permalink: atomicglue.co/glossary/https

Schedule a call

30 min · Video call

1
Date
2
Time
3
Details