Properties of an object are just like variables.

Copying - Making a copy of an existing object.Comparison - Comparing two different objects.Iteration (Enumeration) - Looping over an object’s keys and values.Deletion - Deleting existing properties.Updation - Updating the values of existing properties.Existence - Whether a property exists in an object.Reading/Retrieving - Reading the value associated with a key.Addition - Adding properties to an object.We are going to examine objects by the kind of operation we can perform on them. JavaScript objects embody those characteristics, but they also have a lot more to them as we shall see. You may come across similar concepts in the form of Associative Arrays, maps, and dictionaries in other languages. The properties are also known as key-value pairs. Here’s how ECMA specification defines an object -Īn Object is logically a collection of properties. Here’s an example representation of “ person” object. In our person example, an object can have 4 properties describing it - first name, last name, DOB, and friends. These properties define the object’s characteristics and behavior. In JavaScript, an object can be thought of as a distinct entity that can have properties associated with it. It only has objects for creating custom data types and associating behavior. However, JavaScript does not have classes (even though it has a class keyword), or structures. Constructs such as classes, structures, unions types etc. In some languages, this question would segue into a discussion about user-defined data types or custom data types. If I create four variables for each datum, representing three persons would require 4 * 3 = 12 variable names. What happens when we want to represent a person as a whole? That is, I want to hold on to first name (String), last name (String), date of birth (Date), and her friends (Collection of Strings). In this case, a collection of characters or a string. In a sense, strings are called primitive values because they can represent only one type of information. In this case, firstName holds and represents the first name of a person. For example - const firstName = 'Arfat Salman'

When we create a variable and assign a value to it, we are holding information in it for later retrieval and processing. Just like other primitive values, objects are values too and they serve the same purpose: Representing information or data.

For each javascript object