for week of September 25, 2006:
Bit (noun) The cutting tool at the base or bottom end of the drill string that breaks up the formation into smaller pieces (cuttings) during drilling. Bits come in various sizes and shapes, and are designed for either soft, medium, or hard formations. Common bit types include hammer bits, tricone bits (including button bits and mill tooth bits), drag bits, and core bits. Some other bit types include the fishtail bit, roller-type bit, three-way bit, two cone, Mother Hubbard bit, star bit, crackerjack bit, pilot bit, spudding bit, side bit, T-bit, Z-bit, and paddy bit.