light soy sauce is usually use to make sumashi soup or simmered foods. when you don't wanna put too much color on food, please use that type of soy sauce. to make sumashi soup, add light soy sauce and tofu in dashi soup. It's delicious.

poo light

poo

i belive light

I agree with the others. Light coloured soy is saltier than the dark version. Dark is often used for dishes that need the rich colour.

colour, taste everything. just taste it

According to Yan Can Cook... Light soy sauce is also known as thin soy sauce; it is lighter in color and saltier in taste than dark soy sauce. Light soy sauce is commonly used for marinating or seasoning dishes; it is also used as a dip. Aside from being darker in color and less salty than light soy sauce, dark soy sauce is also referred to as black soy sauce and is used in sautéing and stewing to give an extra touch of sweetness and color.

light soy sauce is for taste, dark is for colour