What is the Difference between overflow and carry binary addition?

You have an adder circuit that can hold a maximum value of 100. With the carry it can hold values up to 199, the carry distinguishes between 31 and 131. But if the sum is greater than 199, you have overflow, because the circuit has no way of telling you what the actual value is.

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you have an overflow when the size of the result doesn't fit to the capacity of the memory sign of the result is different from what is expected (for example, getting a negative result when adding 2 positive numbers) The carry out occur when the size of the result doesn't fit to the capacity of the memory, yet its sign is correct.