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Drupal is an open source content management system written in PHP, originally developed by Dries Buytaert.

PHP is a scripting language for creating websites.

Java is a general-purpose language originally developed by Sun Microsystems.

Microsoft's Active Server Pages technology on the .NET framework.

JavaScript is a lightweight, object-oriented, cross-platform scripting language, often used within web pages.

jQuery is a JavaScript library that simplifies HTML document traversing, event handling, animating and Ajax interaction. Originally developed by John Resig.

Nginx (pronounced as "engine X") is a lightweight open source web server developed by Igor Sysoev.

The Apache HTTP Server is an open source web server by the Apache Software Foundation.

Ubuntu is a Linux distribution.

Acquia provides Drupal hosting.

Amazon is a US-based e-commerce and cloud computing provider.

Akamai provides a content delivery network. This includes the former brands Instart Logic and StackPath.

Cloudflare provides DNS servers and other web services.

Let’s Encrypt is a free, automated, and open certificate authority provided by the Internet Security Research Group.

Google Analytics is a free service to get detailed statistics about the visitors of a website, provided by Google. This includes the Ads conversion tracking and the Floodlight services.

The Google Advertising network consists of AdSense, DoubleClick and other services.

The Google Tag Manager is a Google service to support webmasters to manage tags on their websites.

AddToAny is a social bookmarking and sharing service.

External Cascading Style Sheets define style rules in a separate CSS file.

Embedded Cascading Style Sheets define a set of style rules in a <style> element within a web page.

Inline Cascading Style Sheets define style rules directly within an (X)HTML element using the style attribute.

Session cookies are temporary cookies, which are deleted when the user closes the browser.

Persistent cookies with an expiration time of up to 1 day.

Persistent cookies with an expiration time between 1 month and 1 year.

HttpOnly cookies are used only in the HTTP protocol and not in client side scripts, which may increase security.

Non-HttpOnly cookies are used in the HTTP protocol and also in client side scripts, which may be a security threat.

Secure cookies are used only via an encrypted connections, which may increase security.

Non-secure cookies may be used via an unencrypted connections, which may be a security threat.

Brotli is a lossless compression algorithm developed by Google.

A strong ETag is an HTTP header field for validation of cached web pages, that indicates a byte-for-byte identical page in the cache.

The Internet Protocol version 6 (IPv6) provides amongst others a vastly larger address space than the preceding version 4. We consider a website to support IPv6 if a 128-bit address is assigned to it, regardless of the content delivered at that address.

HTTP/2 is the second major version of the HTTP network protocol.

HTTP Strict Transport Security (HSTS) defines a mechanism enabling web sites to declare themselves accessible only via secure connections.

The websites redirects visitors to its www subdomain, e.g. from example.com to www.example.com.

The websites redirects visitors to use SSL encryption, e.g. from http://example.com/ to https://example.com/.

The Open Graph protocol, originally developed by Facebook, is an RDFa-based format that enables any web page to become a rich object in a social graph.

Twitter/X Cards enable automatic attachment of photos, videos and media elements to tweets.

Generic RDFa (Resource Description Framework in attributes) is RDFa without further specialization.

JSON-LD (JavaScript Object Notation for Linked Data) is a method of encoding Linked Data using JSON.

HTML5 is the fifth revision of the HTML standard.

UTF-8 (8-bit Unicode Transformation Format) is a variable-length character encoding for Unicode, which is backwards compatible with ASCII.

PNG (Portable Network Graphics) is a lossless compression image format, suitable to store graphics with uniformly colored areas, and originally introduced as a free, open-source successor of GIF.

JPEG (Joint Photographic Experts Group) is a lossy compression method suitable to store photographic images.

Scalable Vector Graphics (SVG) is an XML-based vector image format.

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