There are many types of candles produced. Generally, they can be classified into two major categories based on their usage purposes: daily-use lighting candles (ordinary candles) and craft candles (special-purpose candles). The lighting candles are relatively simple, usually white rod-shaped candles. Craft candles can be further classified into many types. Firstly, they can be divided into two categories: jelly craft candles and scented craft candles. Generally, due to the addition of ingredients, it can display various colors (such as birthday candles), and its shape can also be made into various forms as needed (such as spiral shape, numerical shape, etc.), integrating novelty, decoration, ornamental value and functionality. The flame of a candle is divided into three parts: the outer flame, the inner flame and the wick. The outer flame has the highest temperature, while the core of the flame has the lowest. In addition, candles can be divided into two types: coarse wax and smooth wax. Generally, the surface of coarse wax often has a smell, with a layer of white frost on it. Different coarse waxes will bring different scents. For example, in the bedroom, some lavender-scented candles can be placed to have a hypnotic and calming effect. In the bathroom, some ocean-scented candles can be placed. In summer, some loose-scented candles can also be placed to repel mosquitoes. Glossy wax, on the other hand, has no odor and its surface is very smooth, making it easy to create beautiful shapes.