A flyweight in Flyweight Pattern is a stateless object that can be shared across objects or maybe classes many times. Obviously, that suggests Flyweight Pattern is a pattern about memory efficiency and maybe performance if the construction of objects is expensive.
Taking drawing snowflakes as an example. Despite real snowflakes being different to each other, when we are trying to draw them onto canvas, we usually have a limited number of styles. However, by adding properties like sizes and transformations, we can create a beautiful snow scene with limited snowflake styles.
As a flyweight is stateless, ideally it allows multiple operations simultaneously. You might need to be cautious when working with multi-thread stuff. Fortunately, ...