It means Fertility Awareness Method.It is an automatic service that the ovulation chart provides. It will mark your ovulation date and give you a temperature coverline if you are taking your bbt.It will work the best if you take your temps every morning at the same time before you get out of bed.I have been using it for 8 months now and love it because now I can tell what day I will O and if my temps fall below the coverline then I know it will be a BFN before I take a HPT.