Flyweight is an object without any state. The name comes from being very light.

If you've been reading either one of the two previous chapters, you may already think of a type of object that should be very light: a data class. But a data class is all about state. So, is it related to the Flyweight design pattern at all?

To understand this pattern better, we need to jump back in time some twenty years.

Back in '94, when the original Design Patterns book was published, your regular PC had 4 MB of RAM. One of the main goals was to save that precious RAM because you could fit only so much into it.

Nowadays, some cell phones have 4 GB of RAM. Bear that fact in mind when we discuss what the Flyweight design pattern is all about.