Newbie's questions

Hi everyone!
I am new to this forum and i have somme noob questions…
1)Who can give me an easy definition of a firmware? Is it like a driver
2) I often read sentences like “the pioneer 111D can be cross flashed to 111L”, what does iy mean?


Take a look here

Sometimes, there are drives with the same identical hardware that are sold as different models simply because have a different firmware (and obviously different prices). Installing a different firmware on a drive can convert the low-price drive into the hi price model. This, however, invalidate warranty.