What does following key word mean?

Questions
#1

as following IR code shows:

// attr [packedB] storage_scope = "global"
allocate packedB[float32x32 * 32 * 1024 * 1]
produce packedB {
  parallel (x, 0, 32) {
    for (y, 0, 1024) {
      packedB[ramp((((x*1024) + y)*32), 1, 32)] = B[ramp(((x + (y*32))*32), 1, 32)]
    }
  }
}
  1. what does parallel mean and what’s used for?
  2. what does ramp mean and what’s used for?
  3. what does this code section mean?

thank you very much~