english: As with everything else, there have been several different standards over the years with many of them coming in the last couple of years.
non_english: うぐぅうぐぅうぐぅうぐぅうぐぅうぐぅうぐぅうぐぅうぐぅうぐぅうぐぅうぐぅうぐぅうぐぅうぐぅうぐぅうぐぅうぐぅうぐぅうぐぅうぐぅうぐぅうぐぅうぐぅうぐぅうぐぅうぐぅうぐぅぐぅうぐぅうぐぅうぐぅ