What does != means

Answer 1

! Is the operator for not. As mentioned: != is doesn't equal. Such as 4 != 3

Answer 2

compare the values on either sides of them and decide the relation among them.

( a != b ) means
If values of two operands are not equal, then condition becomes true.

Answer 3

simply put: "!=" = does not equal

Answer 4

Unequal
4 != 2

Answer 5

not equal