Which classes in Java provide socket functionality?

// The class represents a client socket. Used to establish a connection with the server.
import java.net.Socket;

// The class represents a server socket. Waits for incoming connections from clients.
import java.net.ServerSocket;

// The class represents an IP address. Used for working with network addresses.
import java.net.InetAddress;

// The class provides access to the local host.
import java.net.Inet4Address;
import java.net.Inet6Address;
import java.net.UnknownHostException;

// Classes for working with input/output streams, necessary for reading and writing data through sockets.
import java.io.InputStream;
import java.io.OutputStream;
import java.io.IOException;

// Class for working with UDP sockets.
import java.net.DatagramSocket;

// Class for working with data packets in UDP.
import java.net.DatagramPacket;