How to get a better understanding of Objects/Classes/Instances

Hi, I'm new to Java and confused, and would appreciate it if someone could help me get a better understanding of objects/classes/instances. The book I'm reading for class just isn't helping me understand the information over these topics. I was just seeing if someone here on this board had any online articles that might've helped them understand these concepts a little better. If you do have any articles or any information that might help me, please feel free to post. Thanks.

The official tutorials explain it pretty well. At least I found their explanations pretty easy to understand.

Lesson: Object-Oriented Programming Concepts (The Java™ Tutorials > Learning the Java Language)

What is that You don't understand?