A Sous Chef is second in command after the Executive Chef in a professional kitchen. This means he or she answers to the chef, but also has some authority over the other kitchen staff. Many of the terms that relate to cooking and cuisine in a professional setting are French. Sous is French for under, so you can see how the sous chef would work directly under the leader of the kitchen.
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A sous chef is the second in command in a kitchen. In French, the term literally means under chef. Sous chefs are an important part of the restaurants they work in, ensuring that everything runs smoothly whether or not the head chef is present. The duties of a sous chef vary widely, depending on the restaurant and its command structure. This position in the culinary world can be extremely demanding, especially since it carries none of the glamor associated with being a head or executive chef.
In order to become a sous chef, someone must undergo professional training. Some people choose to undertake training at a culinary school, while others prefer to learn on the ground by working their way up the restaurant food chain. Some restaurants prefer sous chefs who have worked their way up in the ranks, since they are sometimes more familiar with all of the tasks which need to be performed in a busy kitchen.