Significantly different from conventional statistical machine translation (SMT) (Brown et al., 1993;Koehn et al., 2003;Chiang, 2005), NMT adopts a big neural network to perform the entire translation process in one shot, for which an encoderdecoder architecture is widely used.
the encoder encodes a source sentence into a continuous vector representation, then the decoder uses the continuous vector representation to generate the corresponding target translation word by word.