ABS()
Array()
ASC()
CHR()
CInt()
CStr()
Date()
DateAdd()
DateDiff()
DatePart()
DateSerial()
DateValue()
Day()
Fix()
FormatCurrency()
FormatDateTime()
FormatNumber()
FormatPercent()
Hour()
InStr()
InStrRev()
Int()
IsArray()
IsDate()
IsEmpty()
IsNull()
IsNumeric()
IsObject()
Join()
LBound()
LCase()
Left()
Len()
LTrim()
Mid()
Minute()
Month()
MonthName()
Now()
Replace()
RGB()
Right()
Rnd()
Round()
RTrim()
Second()
Space()
Split()
Sqr()
strComp()
String()
StrReverse()
Time()
TimeSerial()
TimeValue()
TypeName()
UBound()
UCase()
VarType()
WeekDay()
WeekDayName()
Year()

Returns the difference in the number of intervals between two dates/times.

Long

DateDiff(timeinterval,date1,date2 [, firstdayofweek [, firstweekofyear]])

"timeinterval" is the time interval to add;
"date1" and "date2" are any valid date/time expression;
"firstdayofweek" and "firstweekofyear" are optional values to specify the first day of the week and first week of year.

response.write "There are " & DateDiff("d", Date, #1/1/2007#) & " days to the New Year of 2007."

There are -1347 days to the New Year of 2007.

yyyy - Year, m - Month, d - Day, ww - week, n - Minute, q - Quarter, y - Day of Year, w - Weekday, h - Hour, s - Second