The last two numbers in a 10XX series steel refer to the percentage of carbon present in the steel, in 100ths of a percent. Thus 1095 means a plain, high carbon, steel containing 0.95% carbon (can't recall if that's by weight, or volume... I'm thinking volume?). In reality, the numbers usually vary plus or minus a few 100ths of a percent, due to the difficulty in mass producing tons of steel with the exact amount of carbon mixed throughout. "Plain carbon" simply means a steel that has such low amounts of of alloying elements ( such as manganese, chromium, molybdenum etc..) that it doesn't qualify as being an "alloy steel". 1095 should make an excellent knife.