# Understanding Objects in JavaScript

## what is an object and why we need them ?

You know that **array is used to store the list of items** . But what happens if there are some other **characteristics {like colour and weight etc }** of that item and we need to store them . It gets complicated right ?  
That's **where the object comes** into play!!!  
In programming, an **object** is **a special "container" that bundles together information(data) and actions (functions) that belong to the respective** I

magine you are describing a person. In an array, it might look like this:  
`var person = ["Ronak", 25, "Karnataka"];` **.**  
Looking at that array, it’s hard to tell what "25" represents. Is it her age? Her favorite number? Her street address?  
here comes the objects it allows you to use **key-value pairs**, giving every piece of data a label (the key) and a value. let us see further you will get know to more what object is .......

## Creating an Object

We create objects using curly braces `{}`. In obove example:

```javascript
var person = {
  name: "ronak",
  age: 25,
  city: "karnataka"
};
```

here the name and age are known as keys and Ronak , 25 and karnataka are the values of the respective keys .

## Accessing Properties

There are 2 types of accessing methods : Dot Notation and Bracket Notation .

*   ***DOT NOTION  
    ***The Dot Notation approach involves using a dot (`.`) and a key to access a property.  
    The syntax: object.key  
    from above example :  
    
    ```javascript
     var home = person.city // output : karnataka
    ```
    

By using dot and the **city** key, `.name`, we get "karnataka " which is the value of the city property.

*   ***BRACKET NOTION***  
    The Bracket Notation approach involves using square brackets, in which you have an expression that evaluates to a value.  
    **The syntax : object\[expression\]**  
    from above example :  
    
*   ```javascript
    var home = person["city"] // output : karnataka
    ```
    

By using square brackets and a **"city"** string expression, `["city"]`, we get "karnataka " which is the value of the city property.

## Updating, Adding, and Deleting

It is as same as we used to do in array !

*   **Updating:** `person.age = 26;`
    
*   **Adding:** `person.isStudent = true;`
    
*   **Deleting:** `delete person.city;`
    

## Looping Through an Object

Sometimes you need to look at every "key" inside an object. For this, we use the `for` loop as we used to do in array .

```javascript
for (var key in person) {
  console.log(key + ": " + person[key]);
}
// This will print:
// name: ronak
// age: 26
// isStudent: true
```

lets see this what you have read untill now !!!

![](https://cdn.hashnode.com/uploads/covers/697720f9aaff412f46e7c283/2cda13e9-3b3f-4db7-acac-57d400ea45f7.png align="center")

THANK YOU!!!