What's the difference between Lo Mein and Chow Mein?

Paul, Generally, the basic difference between the 2 noodles is one is boiled (lo mien) and the other is stir fried (chow mien). However, if you really dwell further then there will be a sparse difference with the ingredients and sauce used in each of the noodles. Chinese food differs with each location or province of China which have arbitrary factors like culture and weather. For example: In the case of Lo Mien, you may find inland China noodles to be red meat base, as fresh shrimps or fish are scarce or limited and most of all uneconomical. Also, the sauce is also different regionally where the north will like thicker (starchy) and blend sauce, the middle will have starchy spicy and sour sauce and the south will have lighter and saltier gravy. As for chow mien, you will find that the difference in the taste and the ingredients used which is much about the same as the above. Also, the types of noodles used in terms of texture and thickness. If I may add, Chinese have noodles on certain parts of the day which is mainly for breakfast and supper. However, with the bristling economy noodles today have become the Chinese fast food where they can have on the go or takeaways and most of all cheaper. What you have in America isn't really authentic to the real Chinese lo mien or chow mien that the Chinese are eating in their country. As old as the Chinese custom and culture, so is their gourmet and you can never experience it till you've actually visit China. So, bon appetit.