# Objects

An object is an collection value and key pair.

**Creating Objects**
- we use  curley brackets {} or object literal to create object.
ex-
```js
let user = {
name: "John",
age: 18
isAdult: true
}
```

### Different Operations perform in objects

1. Accessing a value
1. Adding a new property
1. Updating a value
1. Deleting the property

**Accessing a value**

For accessing value from an object.

we use 2 operator
- Dot Operator
- Sqaure brakcet operator

Dot Operator( . )

The dot Operator does only one things
is to access the value

ex-
```js
let user = {
name: "John",
age: 18
isAdult: true
}
user.name
"John"
```
Square brackets( [] )

The square brackets does two things computes the value and access it 
 
when to use square brackets??
- when there is space 
- other symbol or number
- or it is stored in a varibale we use it

ex
```js
let user = {
name: "John",
age: 18
isAdult: true
}

 
user[name]
"John"
```

**Adding a new property**

To Add new property
- name of the object follwed by dot ( . ) operator
- name of the key

ex-

```
- Using dot operator
user.city = "London"
"London

- Using sqaure bracket
user["batch"] = 8
"batch"

if we access user

user

age: 18
city: "london"
name: "John"
isAdult: true

```

**Updating a value**
- When the key doesn`t exist it create new property
- if key exist it will update the property

ex-
```js
user.age = 26
<. 26

if we access the user
user: 

age: 26 (age is update from 18 to 24)
city: "London"
batch: 8
is Adult: true
name: "John"
```

**Deleting a Key**
- delete is speacial keyword to delete a property of an object.
- delete followed by name of object and key want to delete

ex-
```js
delete use.city
<. true

user

age: 26 (age is update from 18 to 24)
batch: 8
is Adult: true
name: "John"

city key and value is deleted
```

### Rules  for naming the key in an object
- when key is an single word don`t put in double quote
- whenever you have multiple word keyname remeber to put in double quotes( " " )
- if you don`t  put in   double quotes( " " ) it shoes an error.