Craig Sanders <cas@taz.net.au> wrote:
linux is complex. as are many of the command line tools and there are thousands of them (with perhaps only a few dozen being so generically useful that they're used daily). it is impossible to know every thing there is to know about linux or the software that runs on it (incl. knowledge about either the existence of particular tools or of some of the more specialised/obscure options and capabilites that they have).
As evidence of complexity, consider the size of Linux in a Nutshell (6th ed., O'Reilly, 2009) - 944 pages, according to amazon.com. Bear in mind that this book summarizes only widely used/available commands and options; it falls a very long way short of completeness. The desired command or option for a given task is not always easy to find, and there are often multiple solutions to a problem, which is one reason why communities such as users' groups are valuable, and why most contributors are likely to learn something new, at least occasionally, from the efforts of participants to help others.