Youtube

   YouTube is an American online video sharing and social media platform launched by Steve Chen, Chad Hurley, and Jawed Karim in February 2005. After Google, YouTube is the most visited website worldwide, with over one billion monthly users.

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.

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.

LiteSpeed

   LiteSpeed Web Server (LSWS), is proprietary web server software. It is the 4th most popular web server, estimated to be used by 4.7% of websites as of August 2019. LSWS is developed by privately held LiteSpeed Technologies. The software uses the same configuration format as Apache HTTP Server and is compatible with most Apache features.

Keep-Alive for 5 secs

   The Keep-Alive general header allows the sender to hint about how the connection may be used to set a timeout and a maximum amount of requests.