Compares two object to determine if they

• Have the same value
• Are located within the same memory

The issue with double equals is that it's dependent on the length of the value you're comparing to. The example shows 2 comparisons. 42's and 420's... though both return back different results. The double equals only work when the integer values are less than 128.

NOTE:
Be careful though, string comparisons can be erratic.
You cannot compare if 2 different objects are the same (e.g. Compare an int and a string)

Checks if the object is an instance of a particular class. It's not bothered about the value associated to it. This is ideal for non-known object types. The compiler will know before hand that a string is an instanceof an Integer. It will simply not compile.

In the example, you can see I have created a Animal, lion, and Sea lion classes. when I run a1 instanceof Animal, it's checking if the Sea Lion class is associated to the Animal class. Because they all extend and the Animal class is the superclass, this will return true. If I queried whether a Lion is an instanceof a Sea Lion, because Lion looks up and cannot find Sea Lion in its higher hierarchy, it will return false.

The equals just checks if the value are the same. It's not bothered on whether both objects remain within the same memory. You do have the additional privilege on overriding this method if you wanted so YOU can determine 'what constitutes to equals' rather than just the value, though that's in another blog

You can see within the example, it doesn't matter if you create new instances (which will placed these 2 values within separate memories, it will only look at the value. The last check determines that the last values are false, thus returning false

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