In theory, sautes and stews are on opposite ends of the culinary spectrum; sautes are cooked with dry heat without the addition of liquid, while stews are cooked entirely in liquid without prior browning. Fricassees fall in the middle; meat is lightly browned then braised in liquid. And stews differ from soups because extended slow cooking over low heat results in a thicker consistency and much less liquid.
In fact, those lines have blurred considerably today. Recipes for dishes called stews often call for browning meat before a slow braise. And at least one stew, Filipino chicken adobo, first braises the chicken, then runs it under a broiler for crisping before returning it to its sauce. As for the line between soups and stews, Belgian waterzooi falls halfway between and is served in soup bowls.