Japanese sesame oil comes in dark and clear. Common cooking oil is the dark one (the picture above). It is made from roasted sesame seeds and has distinctive aroma and flavor. When a Japanese recipe calls for sesame seeds, usually referring to this dark one.
Clear sesame oil 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 get.
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. Expensive tempura restaurants still use sesame oil to fry battered fresh sea food.
A brand of Japanese sesame oil is renowned in Eastern Asian countries. It is easy to find Japanese sesame oil at Asian grocery stores.