What is the difference between instant variable and instance variable?

Plz help

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The title makes no sense.

What is the difference between instant variable and instance variable?

Where did you see the term: instant variable? I've never seen it.
What does google return for "instant variable"?

I have seen it in our book.

Look in the book's index or ask google.

Instance variable is a variable defined in the class also known as the class variable. And i guess you meant to say constant instead of instant?

So I think it is wrong in the book.