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

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.

China Telecom (China Telecommunications Corporation) is a Chinese state-owned telecommunication company.

NetEase (also known as 163.com) is a Chinese internet technology company.

China Telecom (China Telecommunications Corporation) is a Chinese state-owned telecommunication company.

NetEase (also known as 163.com) is a Chinese internet technology company.

HiChina is a Chinese internet services provider owned by Alibaba.

NetEase (also known as 163.com) is a Chinese internet technology company.

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

The SSL certificate is invalid because it is not issued for the domain where it is used.

Umeng is a Chinese provider of online web traffic statistics, formerly operating under the name CNZZ.

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.

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

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

Gzip (GNU zip) is a file compression algorithm.

Brotli is a lossless compression algorithm developed by Google.

A weak ETag is an HTTP header field for validation of cached web pages, that indicates a semantically equivalent 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.

HTML5 is the fifth revision of the HTML standard.

Transitional version of XHTML.

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.

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