Returns the last date of the month in the given date parameter, i.e. when the type received is date, it returns a date value, and when the type received is datetime, it returns a datetime.
EoM(date-expression | datetime-expression)
Supposing the Language is set to English:
Result: 01/31/98 10:30:12 if Now() = 01/10/98 10:30:12
Date1 = EoM(Now())
Result: 01/31/98 if Now() = 01/10/98 10:30:12 and Date1 is a date type attribute
TimeZone Support - General Considerations