How much do I know about Pencils?

Day 13, Kathmandu, Nepal

We start our first writing by pencil. But how much we know about it. Like who and where it was first used? How many types of pencils are available in the market?

We usually do not care about these facts. This may be because of we discontinue to write with pencil after four or five class in the school and starts using pens.

Today, I found, I am also unaware of these facts and know less about the pencil although I am still using pencil to sketch to do arts as a part of my hobby. I should have known more facts but it may be due to I am not professional artist.

To fulfill the blank spaces in my Brain about the knowledge of the pencil, I just type "pencil" on Google search bar and there displayed about 2 billion one hundred ninety million records just in 0.49 seconds and on the top of the list it was Wikipedia.
So surfing on some of the top listed websites, I now know some of the facts about pencil.

• Nicolas-Jacques Conté was the first to invent modern pencil in 1975.
• The pencil cores made by mixing Graphite and Clay. The different ratio between these two substances makes the hardness and softness of the pencil. 
• It is easily erasable due to mixing of clay.
• The thin wooden casing is done on almost all pencil
• The hardness and softness are defined by symbols and uses H, F, HB and B
• The standard pencil (common) is symbolized as HB. 
• Other types of pencils are Charcoal Pencil and Carbon Pencil. 

Now I have to go to market in search of the various types of Pencils to do my art sketches. Without them, I will not be able to good sketcher(I think).

I hope above information will be useful to you also. Please do comment on the comment section if you have any.

Chart to illustrate the Hardness and Softness  of the pencils and their symbol