Pencils made from graphite come in 16 degrees of hardness, which are usually indicated somewhere on the side of the pencil. "B" stands for black, indicating the pencil is soft, and "H" stands for hard. "HB", therefore, stands for "Hard Black". Pencils may also be labelled "F", meaning firm.

"B" pencils come in varying degrees of softness, which are appropriately labelled 2B through to 8B. Similarly, hard pencils range from 2H to 6H. "H" pencils usually produce thin, grey lines, whereas "B" pencils are darker and more suitable for shading.

HB pencils are typically used in schools, particularly on exam papers because the shade of grey is easy to detect when scanned into computers for grading. Artists usually prefer "B" pencils when drawing, except for technical drawings, for which "H" pencils are more suitable.

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