JavaScript: Operators
Before we move on, let's take a look at the basic terminology. Operation signs such as + are called operators. They perform operations on certain values (operands). Operators are usually represented by one or more symbols, but occasionally, they can be represented by a word. Most of the operators are identical to those you'll have seen in math class.
console.log(8 + 2);
Here the + is an addition operator, 8 and 2 are operands.
The addition operation has two operands, positioned to the left and right of the operator +. Operations with two operands are called binary operations. If at least one operand is missing, for example, 3 + ; then the program will throw out a syntax error.
Besides binary operations (not operators) there are unary operations (with one operand) and even ternary (with three operands)! Moreover, operators may look the same but denote different operations.
console.log(-3); // => -3
In the example above, the unary operation applies to 3. An interpreter will read it as follows: the minus operator tells it to take the number 3 and find the opposite, which is -3.
You might be a bit confused since -3 is both a number and an operator with an operand, but that's simply how programming languages work.
Instructions
Write a program that calculates and prints the difference between 6 and -81.
Tips
Definitions
Arithmetic operations are addition, subtraction, multiplication and division.
Unary operation is an operation with only one operand. For example,
-3is an unary operation to get the number which is opposite to 3.Binary operation is an operation involving two operands. For example,
3 + 9.