javaScript?.Fundamentals

Here’s a few things to know when getting started with Javascript

Variables

Variables are used to store data, like the price of a item

let and const are used to declare variables

Variables declared with const can not be updated later in your code, variables declared with let can be updated throughout your code.
Use const to store data you don’t expect to change, like your first name

Console Log

console.log is used to view data in the terminal. console.log will be your best friend when you run into bugs. You will have the ability to log variables into the terminal to see where the error is coming from

What type of data can be stored in a variable?

JavaScript has 7 primitive data types & 1 non primitive data type

String

• A sequence of text wrapped around double quotes: "", single quotes: '', or backticks: ``

If you’re storing a string with double quotes within, use single quotes or backticks

You can also add other variables into a string using string interpolation. To use string interpolation you must

• wrap your string in backticks
• add a dollar sign
• add curly braces
• write your variable inside of the curly braces

Number

• A number is just a number, numbers do not need to be wrapped in quotes like a string.
• Decimal numbers are called floats

Boolean

• True or False.

undefined

• Variables declared with no value will be undefined.
• Variables declared with undefined will have a value of undefined

null

• An empty or a unknown value

• Unlike the undefined keyword we are defining a variable with a value of nothing.

Bigint

• A number too larger to be stored in javascript's number data types

Symbol

• A value that is unique and unchangeable

Non primitive data types / Collections of data

Object

• Objects are written with curly brackets and hold {key : value} pairs..

• An object's key is known as the property (the title of the value its attached to)

• value can = any javascript data type | primitives and non primitives

• We can use Dot Notation to access a objects property and we will get the value in return - ex: object.property

Array

• Arrays are "list-like" objects that store multiple data types into a collection
• Arrays are written with brackets [] and hold multiple data types that are separated by commas [1,"a",true,null]
• Data in a array can be accessed individually by its index (numbered position in a list, javascript counts from 0) using bracket notation - ex: array[0]

Operators

• Operators are symbols used to preform operations on values and variables.

Assignment Operator:

• Used to assign values to variables =

Arithmetic Operators

• Used to preform arithmetic calculations

Using += or any arithmetic, assignment operator combination pair will update our initial variables value += -= *= /= %=

Comparison operators

• Used in logical statements to determine equality of values or variables, returns a true or false boolean value

• The equal to operator (==) will convert strings into numbers and compare values regardless of data type
• The strictly equal to operator(===) will only return true if both values are equal and have equal date types
• The not equal to operator(!=) will n

Logical Operators

• Used to determine the true or false logic between variables and values (&&) , (||), (!)

• both values on each side of the and operator must be true for us to get a return value of true

String Operators

• Add strings together. We can combine two strings into one using the + operator or the += operator

JAVASCRIPT FUNDAMENTALS PART 2... COMING SOON