What is the difference between "instantiated" and "initialized"?

Question

I've been hearing these two words used in Microsoft tutorials for VB.NET. What is the difference between these two words when used in reference to variables?

Answer 1

A variable is initialized with a value. An object is instantiated when memory is allocated for it and it's constructor has been run.

For instance here is a variable:

Dim obj as Object

This variable has not been initialized. Once I assign a value to the obj variable, the variable will be initialized. Here are examples of initialization:

obj = 1
obj = "foo"

Instantiation is a very different thing but is related since instantiation is usually followed by initialization:

Dim obj As New Object()

In the preceding line of code, the obj variable is initialized with the reference to the new Object that was instantiated. We say that the new Object was instantiated because we have created a new instance of it.

Now I believe that VB.NET makes this a lot more confusing than C# because it is not clear that an assignment is taking place in the code above. In C# it is much clearer that there is both an instantiation of an instance and an initialization of a variable:

Object obj = new Object();

Answer 2

Instantiated means that an instance of the object has been created. Initiated means that that same object has done some initialization.

Answer 3

When you instantiate a class or object, you're creating a new instance of it, or allocating memory to "hold" one. Initializing that object would be the instructions that are performed during instantiation.

Answer 4

To initialize something is to set it to its initial value. To instantiate something is to create an instance of it.

Often this is the more or less same thing. This:

SqlConnection conn = new SqlConnection();

instantiates a SqlConnection object, and initializes the conn variable by setting it to the that instance.

Since an object's constructor also sets the object's properties to their default values, it's often correct to say that instantiating an object initializes it. (Misleading, if the object exposes a method that you have to explictly call to initialize it after it's instantiated, as is sometimes the case.)

Answer 5

Instantiation is when you create an instance of a class. That instance is then an object, and you can set its properties, or call methods on it (tell it to do things).

Initiation is when you set up a set of initial conditions for something. That something might be an object, where you tell it to initiate itself, or just a variable to which you assign a value.

An object might initialise some other things, or even instantiate other objects as part of its initiation.

The difference is that instantiation is creation of a thing that can do stuff; initiation is stuff that gets done.

Answer 6

*Instantiation means to create an instance for a class or object.Initialization means to initiate the same object or class for any purpose.*