The European producer Koh-I-Noor was the first to introduce a yellow pencil.  It was first used in the 1890's.  The graphite came from China.  American pencil makers wanted a special way to tell people that their pencils contained Chinese graphite. Yes, I usually do like to use a average yellow pencil just because they are cheap and easy to get a hold of.  I tend to write with both pens and pencils on a daily basis.  I don't really have a favorite.  I think pencils are great for doodling because with them you can erase if you mess up. I guess you can call me a pencil doodler, because I draw maps in my free time at home.  It is a good idea to always use a pencil on math assignments or other school assignments, so you can erase if you need to.  I believe that there will always be a need for pencils, unless someone invents a new electronic pencil that is cheap.  

http://pencils.com/why-are-pencils-yellow/
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