Apache is the widely known term for the Apache HTTP server, a very commonly used web server software maintained by the Apache Software Foundation. If your question is about other Apache software such as Tomcat or log4j, http://stackoverflow.com/ is a better choice.
Apache HTTP Server is one of the most widely used web server software programs used to host web site content. Use this tag for questions related to issues related directly to configuration, troubleshooting, error messages, etc. from the Apache HTTP web server.