Understanding JavaScript Operators and Dynamic Typing

Hey everyone!
In today’s JavaScript class, I learned some very interesting and fun topics that form the core of how JavaScript handles calculations, values, and operations. Here's a summary of what I learned today

Concatenation in JavaScript

Concatenation means joining two or more strings.
In JavaScript, if you use + between a string and a number, it will combine them as a string.

console.log("10" + 5); // Output: "105"

Dynamic Typing

JavaScript is a dynamically typed language, which means:

• You don’t need to declare the data type of a variable.
• The type can change automatically based on the value assigned.

let value = "10" + 5;  // value is now a string: "105"

JavaScript Operators

We learned about different types of operators, especially:

NaN – Not a Number

NaN stands for Not a Number. It shows up when a calculation doesn’t result in a valid number.

let result = "hello" * 5;
console.log(result); // NaN

Pre & Post Increment/Decrement

Post-Increment (x++)

The current value is used first, then incremented.

let x = 5;
console.log(x++); // Output: 5
console.log(x);   // Output: 6

Pre-Increment (++x)

The value is increased first, then used.

let x = 5;
console.log(++x); // Output: 6

Post-Decrement (x--)

let y = 10;
console.log(y--); // Output: 10
console.log(y);   // Output: 9

Pre-Decrement (--y)

let y = 10;
console.log(--y); // Output: 9

Summary

Here's what I learned today:

• Concatenation joins strings and numbers.
• JavaScript uses dynamic typing.
• NaN means Not a Number.
• Arithmetic operators perform basic math.
• Pre/Post Increment & Decrement help us increase or decrease values easily.