PHP

PHP Usage Statistics · Download List of All Websites using PHP

PHP is a widely used general-purpose scripting language that is especially suited for Web development and can be embedded into HTML.

Varnish

Varnish Usage Statistics · Download List of All Websites using Varnish

Varnish is a web accelerator / reverse proxy caching server.

Varnish Server

Apache

Apache Usage Statistics · Download List of All Websites using Apache

Apache has been the most popular web server on the Internet since April 1996.

CentOS

CentOS Usage Statistics · Download List of All Websites using CentOS

CentOS is an Enterprise-class Linux Distribution derived from sources freely provided to the public by a prominent North American Enterprise Linux vendor. CentOS conforms fully with the upstream vendors redistribution policy and aims to be 100% binary compatible.

OpenSSL

OpenSSL Usage Statistics · Download List of All Websites using OpenSSL

The OpenSSL Project is a collaborative effort to develop a robust, commercial-grade, full-featured, and Open Source toolkit implementing the Secure Sockets Layer (SSL v2/v3) and Transport Layer Security (TLS v1) protocols as well as a full-strength general purpose cryptography library.

HTML5 DocType

HTML5 DocType Usage Statistics

The DOCTYPE is a required preamble for HTML5 websites.