The primary difference between lo mein and chow mein lies in their cooking methods and texture. Chow mein means "fried noodles" and typically involves stir-frying boiled noodles in a hot wok with minimal sauce, resulting in noodles that are either slightly oily or crispy. Lo mein means "tossed noodles" and consists of fully cooked noodles that are mixed with vegetables, proteins, and a generous amount of sauce, making lo mein noodles soft, smooth, and saucy. Other distinctions include:

• Chow mein noodles can be either fresh or dried egg noodles, while lo mein traditionally uses fresh egg noodles.
• Chow mein uses less sauce and focuses on noodle texture, either crispy or lightly fried, while lo mein is saucier and the noodles are softer because they are boiled and then tossed with sauce.
• Chow mein dishes keep vegetables and protein minimal to highlight the noodle texture; lo mein has more mixed-in ingredients.

In summary: chow mein is fried (with crispier or lightly fried noodles and little sauce), while lo mein is tossed or mixed with sauce and ingredients after the noodles are fully boiled, resulting in softer, saucier noodles.