1. Apache is the leading internet web server, with over 60% market share, according to the Netcraft survey. Several key factors have contributed to Apache's success: The Apache license. It is an open source, BSD-like license that allows for both commercial and non-commercial uses of Apache. Talented community of developers with a variety of backgrounds and an open development process based on technical merits. Modular architecture. Apache users can easily add functionality or tailor Apache to their specific enviroment. Portable: Apache runs on nearly all flavors of Unix (and Linux), Windows, BeOs, mainframes... Robustness and security. Many commercial vendors have adopted Apache-based solutions for their products, including Oracle, Red Hat and IBM. In addition, Covalent provides add-on modules and 24x7 support for Apache. The following websites use Apache or derivatives. Chances are that if Apache is good enough for them, it is also good enough for you. Amazon.com Yahoo! W3 Consortium Financial Times Network solutions MP3.com Stanford From the Apache website: The Apache Project is a collaborative software development effort aimed at creating a robust, commercial-grade, featureful, and freely-available source code implementation of an HTTP (Web) server. The Apache project has grown beyond building just a web server into other critical server side technologies like Java or XML. The Apache Software Foundation, described in the next section, serves as an umbrella for these projects. From Apache Overview HOWTO

2. Versatile, high-performance HTTP server The most popular server in the world, Apache features a modular design and supports dynamic selection of extension modules at runtime. Some of its strong points are its range of possible customization, dynamic adjustment of the number of server processes, and a whole range of available modules including many authentication mechanisms, server-parsed HTML, server-side includes, access control, CERN httpd metafiles emulation, proxy caching, etc. Apache also supports multiple virtual homing. Separate Debian packages are available for PHP3, mod_perl, Java Servlet support, Apache-SSL, and other common extensions. More information is available at http://www.apache.org/. From Debian 3.0r0 APT