Objects in JavaScript.
In real-world applications, data is rarely stored as single values. Most of the time, we need to store related information together. For example, if we want to store information about a person, we might need name , age , city etc. Instead of creating separate variables for each value, JavaScript allows us to group them together using objects.
What are Objects?
An object is a data structure used to store multiple related values.Objects store data in key–value pairs.
Example:
{ key: value }
Think of it like a profile card.
Example:
const person = { name: "Hammad", age: 22, city: "Multan" };
Here the keys are name , age and city and vlues are the Hammad , 22 , Multan. Each key represents a property, and each property has a value.
Why Objects are needed:
Imagine storing this data without objects:
const name = "Hammad"; const age = 22; const city = "Multan";
Now suppose you want to store data for 10 people.
Managing separate variables becomes messy.
Objects allow us to group related data together:
const person = { name: "Hammad", age: 22, city: "Multan" };
This makes code organized and easier to manage.
Array vs Object:
Both arrays and objects store multiple values, but they work differently.
Array : Stores values using indexes.
const fruits = ["Apple", "Banana", "Mango"];
Accessing values: console.log(fruits[0]);
Output: Apple
Object : Stores values using keys.
const person = { name: "Ali", age: 25 };
Accessing values: console.log(person.name);
Output: Ali
Creating Objects: We create objects using curly braces {}.
Example:
const person = { name: "Hammad", age: 22, city: "Multan" };
Each property is written as: key: value
Properties are separated by commas.
Accessing Object Properties:
There are two ways to access object properties.
Dot Notation: This is the most common method. console.log(person.name); console.log(person.age); Output : Hammad 22
Bracket Notation: We can also use square brackets. console.log(person["city"]); Output : Multan. Bracket notation is useful when the property name is stored in a variable. Example : const key = "name";
console.log(person[key]);
output : Hammad
Diagram :