A pointed metal instrument used for making lines on work.
A pencil-like tool with a steel point; used to remove the emulsion of a negative, for engraving rules or adding other fine detail. to top
A tagging instrument, usually made out of a diamond drillbit, used to physically engrave one's name on buses and mass transit vehicles. Considered by some writers to be more destructive than is needed. Sandpaper is sometimes used to tag buses in the same manner--it too is considered mass destruction.
Scribers are hand tools used in the metal trades to mark lines on workpieces, prior to machining. This is used instead of pencils as the marks from pencils cannot be seen as clearly as Scriber marks. They consist simply of a rod of high-carbon steel, in its hardened state, that has been sharpened to a point at one or both ends.