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.

Nginx

   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.

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.

Google Hosted Libraries

   The Google Hosted Libraries is a stable, reliable, high-speed, globally available content distribution network for the most popular, open-source JavaScript libraries.

Stackpath BootstrapCDN

   BootstrapCDN is a public content delivery network. Users of BootstrapCDN can load CSS, JavaScript and images remotely, from its servers,encompasses MaxCDN and NetDNA

jquery 2.0.0

   JavaScript library for DOM operations

Server partial requests support

   The Accept-Ranges response HTTP header is a marker used by the server to advertise its support of partial requests. The value of this field indicates the unit that can be used to define a range.

Font Awesome 4.3.0

   Font Awesome is a font and icon toolkit based on CSS and LESS. It was made by Dave Gandy for use with Twitter Bootstrap, and later was incorporated into the BootstrapCDN.