Yellow L & C Hardtmuth Koh-i-noor HB pencil used by engineers working on CSIRAC. This pencil may well have been used in the preparation of programs during the period that CSIRAC was at the University of Melbourne.

Pencils were used sometimes in preference to fountain pens; the use of ball-point pens was only then becoming commonplace.

The following has been copied from - accessed 10 December 2008:
Many pencils across the world and almost all in Europe are graded on the European system using a continuum from "H" (for hardness) to "B" (for blackness), as well as "F" (for fine point). The standard writing pencil is graded HB.

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