The difference between per kilogram 18 yuan and per kilogram 10 yuan.

There are two kinds of sweets mentioned here, each kilogram 18 yuan and each kilogram 10 yuan. It can be seen that the prices of these two kinds of sweets are different. From the price point of view, candy per kilogram 18 yuan is more expensive than candy per kilogram 10 yuan.

However, we can't fully understand the difference between these two kinds of sweets only from the price, we need to further understand their other characteristics. The possible differences are as follows:

1. Brand and taste: These two kinds of sweets may come from different brands, and they may have different tastes and packaging. Brand and taste are important characteristics of candy, and different people may have preferences for different brands and tastes.

2. Composition and nutritional value: Different candies may use different raw materials and formulas, and their composition and nutritional value may be different. Some sweets may be added with more vitamins, fiber and other nutrients, while others may pay more attention to taste and sweetness.

3. Origin and quality: The two kinds of candy may come from different production places, and their quality and production technology may be different. Some candies may use higher quality ingredients and techniques, while others may be of lower quality. This may affect the taste and shelf life of candy.

To sum up, we can't accurately determine all the differences between the two kinds of sweets only by the price per kilogram 18 yuan and per kilogram 10 yuan. We need to know more about the brand, taste, ingredients, nutritional value, origin and quality of candy, so as to compare and distinguish the two kinds of candy in detail.