Private Cache-Control Header

   The Cache-Control general-header field is used to specify directives for caching mechanisms in both requests and responses. Caching directives are unidirectional, meaning that a given directive in a request is not implying that the same directive is to be given in the response.

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

SEO Robots : Allow to index and follow website links

   Meta robots tag is a tag that tells search engines what to follow and what not to follow.

Block Content Sniffing

   The X-Content-Type-Options response HTTP header is a marker used by the server to indicate that the MIME types advertised in the Content-Type headers should not be changed and be followed. This allows to opt-out of MIME type sniffing, or, in other words, it is a way to say that the webmasters knew what they were doing.

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.

Facebook Pixel

   The Facebook pixel is an analytics tool that allows you to measure the effectiveness of your advertising by understanding the actions people take on your website.

SPF

   The Sender Policy Framework (SPF) is an email-authentication technique which is used to prevent spammers from sending messages on behalf of your domain. With SPF an organisation can publish authorized mail servers.

Google Tag Manager

   Google Tag Manager is a tag management system created by Google to manage JavaScript and HTML tags used for tracking and analytics on websites (variants of e-marketing tags, sometimes referred to as tracking pixels or web beacons.

Disable Telephone link in HTML on Mobile Devices

   Telephone links are a thing. Like an anchor link you tap to (probably) go to another page, these are links you tap to call a number on a phone-capable device.

Viewport - Width

   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.

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.

jquery 3.3.1

   JavaScript library for DOM operations

Cdnjs

   cdnjs is a CDN host for opensource libraries

Nginx 1.16.1

   Nginx is a web server which can also be used as a reverse proxy, load balancer, mail proxy and HTTP cache. The software was created by Igor Sysoev and first publicly released in 2004. A company of the same name was founded in 2011 to provide support and Nginx plus paid software.