The unary minus operator (-...) will first convert its operand into Number in the same way as the unary + operator, detailed in the last section, and will then negate it:
-55; // => -55-(-55); // => 55-'55'; // => -55
Its usage is fairly straightforward and intuitive, although, as with unary +, it's useful to disambiguate cases where you have a unary operator next to its binary operator counterpart. Cases like these can be confusing:
number - -otherNumber
It is best, in these situations, to lend clarity with parentheses:
number - (-otherNumber)
The unary minus operator is usually only used directly with a literal number operand to specify a negative value. As with all other arithmetic operators, we should ensure ...