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.

Meta Description

   A meta description is a 160-character snippet, a meta tag in HTML, that summarizes a page`s content. this website is having meta description of the following : Watch World War 2 aircraft pilot training films for free over the 'Net for the A-20, B-17, AT6/SNJ, P-51, P-38, P-39, P-40, F4U, F6F, P-47, P-6 1, B-29, B-24, B-25, A-26, B-26 & more in broadband video. See charts, pictures, diagrams and performance specifications from World War II pilot's manuals.Order WWII aviation videos online & save up to 50%! A Yahoo Pick of the Week.

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.

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.