The document compares and evaluates three neural network approaches - deep neural network (DNN), deep belief network (DBN), and convolutional neural network (CNN) - for handwritten digit recognition. The approaches are evaluated based on factors like accuracy, performance, and execution time using standard datasets. The results show that DNN achieved the highest accuracy rate of 98.08%, while each approach had an error rate of 1-2% due to similarities between some digit shapes.