Please explain me following lines

Hi All,

Please explain me following two lines:

if (combined.Length != 0)

prefix += appendAnd ? " and " : " ";

In above line what is the use of '?' and ':'

Thanks and regards,

Swapnil.

That is aTernary Expression.

If means,

If the var appendAnd evaluates to True

then perform the operation (+=) with the data directly after the question mark

else

perform the oprtation with the data after the colon :