You first specified this directory during installation. Hostname is the URL clients will use to access your server. Port is the port on your system that the server listens to for HTTP requests. Error log is the name and path of the server's error log file. Minimum threads is the minimum number of threads the server uses to answer requests.
Maximum threads is the maximum number of threads the server uses to answer requests.
DNS shows whether DNS is enabled or disabled. Security shows whether SSL is enabled or disabled. The server's content settings depend on how you've configured your server. Common server content settings include the server's document directory, its index filenames, name and location of its access log, and default MIME type. You can enable DNS usage using the Server Manager.