Batch file FOR /f tokens

Can anyone please explain exactly how the following code works, line by line. I'm really lost. I've been trying to learn how to use the FOR command but I don't understand this.

@echo off

for /f "tokens=* delims= " %%f in (myfile) do (
  set line=%%f
  call :processToken
  )
  goto :eof

:processToken

  for /f "tokens=1* delims=/" %%a in ("%line%") do (
  echo Got one token: %%a
  set line=%%b
  )
  if not "%line%" == "" goto :processToken
  goto :eof