Different methods of deprectation according to income tax?

Is a very lengthy, almost exhaustive topic. There are many methods allowed and lives available for differenct classes of assets, and in fact elections that can be made every year...etc. It is fair to say, there is alost always a faster, sometimes much faster, method than books available. The difference in Deprec is many Cos largest Book to Tax M-3 (timing dfference). Of course, it is only a timing difference as the faster deprec causes a lower basis in the asset, which when sold or disposed causes more gain (or less loss), which increases income oon that event....and any accelerated deprec taken must be replaced at ordinary rates (not capital) which is how it was taken.