People would often have to cram and do immediate research to get a full understanding of a particular area of concern. People have to resort to doing search queries, resorting to periodical content and even reaching down to known reference books such as an Encyclopedia or the Almanac, to be able to get a full overview of what a particular topic or subject matter is all about.
While such is a given, there are people who can give their two cents worth of opinions and stored knowledge as well. This all stems from these individuals who have put emphasis on certain areas of interest that include electronics, travel and history. Not all people are expected to invest such effort and time since every individual would want to cater to a lot of things with nothing particular to specialize in.
Ideally, such knowledge from people which are tagged geeks at some time would go as far as holding technical information such as content, components and workflow processes. Such areas are not given much attention in the normal phase of life. But such are investments to which one day; such stored and solicited knowledge shall be of big use towards other people and big entities who seek better knowledge as well.