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.

PHP 4.4.9

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

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.

Apache 2.4.18 |Operating System:Win64

   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.

No Cache Content

   Forces caches to submit the request to the origin server for validation before releasing a cached copy.

Must Revalidate HTTP Cache-Control

   Indicates that once a resource has become stale (e.g. max-age has expired), a cache must not use the response to satisfy subsequent requests for this resource without successful validation on the origin server.

Chunked transfer encoding

   Chunked transfer encoding is a streaming data transfer mechanism available in version 1.1 of the Hypertext Transfer Protocol (HTTP). In chunked transfer encoding, the data stream is divided into a series of non-overlapping "chunks"