We discuss mode-entangled states based on the optical transverse modes of the optical
field propagating in multi-mode waveguides, which are classical analogs of the quantum
entangled states. The analogs are discussed in detail, including the violation of
the Bell inequality and the correlation properties of optical pulses' group delays.
The research on these analogs may be important, for it not only provides useful insights
into fundamental features of quantum entanglement, but also yields new insights into
quantum computation and quantum communication.