# Why are the unary operators unary operators?

(Maybe the title is a little stupid..)

I completely understand the usages of the unary operators introduced in this video, but some of them seem to me binary operators.

Let's say for an example.

var a: Int = 1

a += 1 a -= 1

In the two lines above, both "+=" and "-=" seem to me binary operators because they connect two operands (a and 1) and are located in between as infix.

Well, the negating operator (var a: Bool = true; a = !a) is for me a unary operator because it only affects one operand (a).

• The logical negation operator (`!`). This inverts a boolean expression, so `!true` is `false`, and `!false` is `true`
• The mathematical negation operator (`-`). This makes a positive number negative, and a negative number positive (example: `-42`)
• The unary plus operator (`+`). This simply returns its value as is. For example `+42` is still just `42`. This operator is entirely useless, but looks nice near a mathematical negation operator when you're choosing if you want something positive or negative