Please explain MOD command

I cant get it. Why and in what situation is MOD required?
please give me an explanation in both words and code.

Well, mod divides a number by another number and then returns the remainder.

13 / 4 = 3 remainder 1 (wich means there is 1 left over).

The age old example is for checking leap years.

lngResult = lngYear Mod 4

If lngResult = 0 Then Msgbox "Leap Year!"

2000 Mod 4 = 500, remainder 0. Mod returns the "0" part, so 2000 is a leap year. Likewise:

2003 Mod 4 = 500, remainder 3. Mod returns the "3", so 2003 <> leap year.

Quote:

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Mod Operator

Used to divide two numbers and return only the remainder.

Syntax

result = number1 Mod number2

The Mod operator syntax has these parts:

Part Description
result Required; any numeric variable.
number1 Required; any numeric expression.
number2 Required; any numeric expression.

Remarks

The modulus, or remainder, operator divides number1 by number2 (rounding floating-point numbers to integers) and returns only the remainder as result. For example, in the followingexpression, A (result) equals 5.

A = 19 Mod 6.7

Usually, the data type of result is a Byte, Byte variant,Integer, Integer variant,Long, or Variant containing a Long, regardless of whether or not result is a whole number. Any fractional portion is truncated. However, if any expression is Null, result is Null. Any expression that is Empty is treated as 0.

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