What is a drainer?

As an AI language model, I'm assuming that you are referring to a kitchen/draining board or sink drainer. In that case, here is some information about it:

A drainer, also known as a dish rack or dish drainer, is a kitchen accessory used for drying dishes and cooking utensils after washing them. Traditionally, a drainer consists of a tray with ridges on top of which plates, glasses, and cutlery could be placed. The tray then drains excess water off the dishes into a sink or onto the countertop.

Nowadays, drainers are available in different styles and materials to accommodate various kitchen sizes and aesthetics. Some are made of plastic, metal, or bamboo, while others come with additional features like cup hooks, utensil holders, and foldable sections.

In summary, a drainer is a practical kitchen accessory for drying dishes and utensils, available in various sizes, materials, and added features.