To learn more about the Apache HTTP Server, refer to the following resources.
Apache HTTP Server documentation — If you have the httpd-manual package installed and the Apache HTTP Server daemon (httpd) running, you can view the Apache HTTP Server documentation. Open a Web browser, and go to the URL http://localhost on the server that is running the Apache HTTP Server. Then, click the Documentation link.
/usr/share/docs/httpd-<version> — The Apache Migration HOWTO document contains a list of changes from version 1.3 to version 2.0 as well as information about how to migration the configuration file manually.