Most of the aromatic plants, including lemon basil, ginger etc., grown in Thailand are used in their dishes to make the food spicy. Thai people use these herbs and spices due to the following two reasons: They love spicy food and, Spices have medicinal purposes.
A major difference noted in Thailand is that they will not use a knife, instead use a spoon. Pieces of meat or fish served here are cut into small portions and that can be eaten with the spoon.
Thai people rarely eat food alone and they share each others' food plates. A plate of rice is served with almost all Thai meals.
On the basis of where you stay in Thailand, they use numerous types of chilies in the dishes they cook. (Thai word for chili is prik.) Thai Chili is the most common type of chili, available almost everywhere in the world. Another type is prik kee nu, a very small, extremely spicy chili, often served as a condiment.
Ginger is another herb that makes your food spicy. You can boil ginger to make a tea and add some sparkle of it to grilled and baked fish.
Chili is also used to make the curry hot. Albeit having several varieties of curry, they use only five types, green, red, yellow, massaman, and penang curries. In order to get the correct flavor for different meats they use different curry. Lemon basil has a great flavor and it will make your food much spicier.