String operations

To concatenate strings you can use “TEXT”, “TEXT” or “TEXT” + “TEXT”

To add variables into the sting you must use ${} inside of ``

let message = "Hello World!";
let variable = 10;
console.log(message, "This is a message from JavaScript");
console.log(`I have ${variable} apples`);

Math Operators

+ Add
- Subtract
* Multiply
/ Divide

these are the 4 basic math operaters as there are many more like floor(), sin(), Math.Random(), and many more Math operaters are mainly used when using 2 Number values and applying the operator to them

let num1 = 10
let num2 = 20

console.log(num1 + num2)
console.log(num1 - num2)
console.log(num1 * num2)
console.log(num1 / num2)

Bool Expressions

false: The boolean value false is considered falsy.
0: The number 0 (zero) is falsy in JavaScript.
NaN: The special "Not-a-Number" value is falsy.
null: The absence of any object or value is falsy.
undefined: A variable that has not been assigned a value is falsy.

Above examples from AI

these are the main ways of showing how a variable is empty which is usefull to disallow some conditions to run or prevent errs

let NextValue = null // this shows that there is no value but one can be added later
let AnotherValue = undefined // this shows that there is no value and one can be added later
let ThirdValue = 10 // this shows that there is a value