Differentiate between <> and <> features of use cases

In Use case diagram kindly differentiate between <> and <> features of use cases? Kindly clarify with some example?

Your question is incomplete and unclear but as per my understanding you want to ask about «uses» and «extend» relationship between use cases.

The «uses» relationship allows us to include the steps from one use case into another use case. Let us take the example of a Online Shopping System.
Any person can visit an online shopping portal and browse some products and place an order. But while placing the order, the system checks whether the person is a registered use or not. So in the above scenario of shopping portal, Place Order is a use case and Identify User is another use case. So when the use case Place Order is invoked this in turn uses the use case Identify User.

The «extend» relationship allows us to modify the behavior of the base Use Case. Suppose we want to sell products that are made to order and require a degree of customer specification. For example, you want to order a dress through online shopping portal. But to buy that dress, you may need to provide your specification to the system like height, dress color etc. Here Place Customized Order is a use case and Provide Specification is another use case. The use case Provide Specification will extend the functionality of use case Place Customized Order here.