Japanese sesame oil comes in dark or clear. Common cooking oil is the dark one (the picture above). It is made from roasted sesame seeds and has distinctive toasty aroma and flavor. When a Japanese recipe calls for sesame oil, usually referring to this dark one.
Clear one is called taihaku-yu. Because it’s made from raw sesame seeds, it is completely odorless, but has the flavor of sesame. It’s more expensive and hard to find.
For me fragrance of sesame oil is always associated with Chinese or Korean food. So that I was surprised to know that tempura was originally deep fried in sesame oil. High end and authentic tempura restaurants still use this fragrant oil to fry battered fresh sea food.
A brand of Japanese sesame oil is very popular in Eastern Asian countries. It is easy to find Japanese sesame oil at any Asian grocery stores.