Viewport - initial-scale

   The viewport is the user`s visible area of a web page. The viewport varies with the device, and will be smaller on a mobile phone than on a computer screen. Before tablets and mobile phones, web pages were designed only for computer screens, and it was common for web pages to have a static design and a fixed size.

Google Analytics

   Google Analytics is a web analytics service offered by Google that tracks and reports website traffic, currently as a platform inside the Google Marketing Platform brand.

Twitter Cards

   With Twitter Cards, you can attach rich photos, videos and media experiences to Tweets, helping to drive traffic to your website.

manifest.json

   The manifest.json file is the only file that every extension using WebExtension APIs must contain.

Apache

   The Apache HTTP Server, colloquially called Apache, is free and open-source cross-platform web server software, released under the terms of Apache License 2.0. Apache is developed and maintained by an open community of developers under the auspices of the Apache Software Foundation.

Character Encoding :UTF-8

   This website is using UTF-8 character encoding in HTML , character encoding is used to represent a repertoire of characters by some kind of encoding system.

Gzip Content-Encoding

   The Content-Encoding entity header is used to compress the media-type. When present, its value indicates which encodings were applied to the entity-body. It lets the client know how to decode in order to obtain the media-type referenced by the Content-Type header.

Vary Header check for User-Agent

   When using the Vary: User-Agent header, caching servers should consider the user agent when deciding whether to serve the page from cache

Vary Header Accept-Encoding

   The Accept-Encoding request HTTP header advertises which content encoding, usually a compression algorithm, the client is able to understand. Using content negotiation, the server selects one of the proposals, uses it and informs the client of its choice with the Content-Encoding response header.

HSTS - Browser HTTPS Only for domain and subdomains

   The HTTP Strict-Transport-Security response header (often abbreviated as HSTS) lets a web site tell browsers that it should only be accessed using HTTPS, instead of using HTTP for domain and subdomains browsers will never connect to your domain using an insecure connection. While the service is hosted by Googlefor 63072000 seconds

PHP 5.6.40

   PHP: Hypertext Preprocessor is a general-purpose programming language originally designed for web development.