Jaggery is a type of raw sugar. It is usually purchased in a large block or small cone. With jaggery, the molasses is never separated from the sugar. This is different from brown sugar, which is usually made by separating the sugar into fully refined sugar, then adding the molasses back in.
Jaggery is an important ingredient in India, Southeast Asia, and Africa. In Indian cooking, it is often used in sweet and in savory dishes. In sweet dishes, jaggery if often used to provide the sugar. In savory dishes, it can be used to balance spicy, salty, or tart flavors.
Lately, I have experimented with “jaggery powder,” which is made from crushed jaggery. It is a much drier ingredient than freshly grated jaggery, and recipes often have to be adjusted to compensate.
You can find jaggery at Indian grocery stores, or in Latin markets where it is called “panela.”