If a cross-reference is to a single word, for example, a command name like this: tar (19.5), the cross reference is probably to an article that introduces that command. Cross references to phrases, like this: writes the verbose information to its standard output (19.8) are to an article that explains more about the concept or problem printed in gray.
Cross references don't necessarily give a complete list of all articles about a topic. We've tried to pick one or a few articles that give the best information. For a more complete list, use the Index.