Thread: is it necessary to use pthread and select for concurrent sockets

hello,
is it necessary to use pthread and select if i want to build a http server and wish to have concurrent client access?
like this code from the gnuc library page (delorie.com/gnu/docs/glibc/libc_340.html)
such as how you might see the comments if i may create a pthread_create when input arrives on the socket and it is not already an established connection,
hope this makes sense,
regards

Code:

while (1)
    {
      /* Block until input arrives on one or more active sockets. */
      read_fd_set = active_fd_set;
      if (select (FD_SETSIZE, &read_fd_set, NULL, NULL, NULL) < 0)
        {
          perror ("select");
          exit (EXIT_FAILURE);
        }

      /* Service all the sockets with input pending. */
      for (i = 0; i < FD_SETSIZE; ++i)
        if (FD_ISSET (i, &read_fd_set))
          {
            if (i == sock)
              {
                /* Connection request on original socket. */
                int new;
                size = sizeof (clientname);
                //do i need to put a pthread_create() here in 
                //order to have concurrent client execution
               //and handle the accepting/recv'ing/sending etc to the socket
               //such as in the normal multithreaded/concurrent server
                new = accept (sock,
                              (struct sockaddr *) &clientname,
                              &size);
                if (new < 0)
                  {
                    perror ("accept");
                    exit (EXIT_FAILURE);
                  }
                fprintf (stderr,
                         "Server: connect from host %s, port %hd.\n",
                         inet_ntoa (clientname.sin_addr),
                         ntohs (clientname.sin_port));
                FD_SET (new, &active_fd_set);
              }
            else
              {
                /* Data arriving on an already-connected socket. */
                if (read_from_client (i) < 0)
                  {
                    close (i);
                    FD_CLR (i, &active_fd_set);
                  }
              }
          }
    }
}