See also:

Load index
Tire data is vehicle-specific and may deviate from the data in the example. In addition to the load bearing index, load index 1 may be imprinted after the letters that identify speed index 6 ...

Traction
Traction is the result of friction between the tires and the road surface. ...

DOT, Tire Identification Number (TIN)
U.S. tire regulations prescribe that every manufacturer of new tires or retreader has to imprint a TIN in or on the sidewall of each tire produced. The TIN is a unique identification number. ...