What Should We Be Looking For On Our Coins? Chime In For A Complete List

I included the following on another thread but thought this might make a new good one. Reply with changes or additions and let's see if we can get a complete list.

Good Lord there is a lot to look for on coins. Business Strikes, Proofs, Matte Proofs, Doubled Dies( Must be thousands and 9 Doubled Die Classes), Key Dates, Semi-Key Dates, Rare Varieties, Coin Grades, Toning (natural or artificial), Cleaned Coins, Over Date, Re-Punched Mint Marks, Over Mint Marks, Mint Mark Styles and in what years, Mint Mark Location, Broken Mint Mark Punch, Inverted Mint Marks, Small Date, Large Date, Coin Types, Full Bell Lines, Full Bands, Full Torch, Wide AM, Close AM, Designer Initials, Design Anomalies, Dropped Letters, Errors, Trail Dies, BIE's, Die Clashes, Lathe lines, Transitional Varieties (Obverse and Reverse), Cuds, Die Cracks, Shattered Die, Collapsed Die, Die Dents, Floating Roofs, Die Chips, Laminations, Split Plating, Missing Clad Layers, Struck on Wrong Planchet, Misaligned Dies, Off Center, Double Struck, Die Rotation, Machine Doubling, Ejection Doubling, Die Flow, Die Abrasion, Die Deterioration, Gas Bubbles, Woodies, RR Rims, Clipped, Struck Through, Feeder Finger Damage, Zinc Rot, Counterfeits, and probably more I missed and yet to be identified. Makes your head hurt looking for all these and what they mean.