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.

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.

WordPress 4.6.1

   WordPress is a content management system based on PHP and MySQL that is usually used with the MySQL or MariaDB database servers but can also use the SQLite database engine.

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.

Vary Header Accept-Encoding

   The Accept-Encoding request HTTP header advertises which content encoding, usually a compression algorithm, the client is able to understand. Using content negotiation, the server selects one of the proposals, uses it and informs the client of its choice with the Content-Encoding response header.