A search engine is a great tool as it provides unlimited information on any given topic.
However, as convenient and prompt as it may seem, it is not all-powerful and absolute.
Derek Vs. Google is a reminder that too much dependence on web search does infact restrict one's knowledge, rather than enhance it.
Questions asked in this section can be better answered through field work and experience.
Google won't help you - unless, ofcourse, you search with the answer, once it is published ;)
In the Railways, what is said to be the first object to be used as the signal light?