Coriander (Coriandrum sativum) is known as Dhania in North India. Out of India it is also known as cilantro, Chinese parsley.
It is a soft plant which grows to 50 cm (20 in) tall. The leaves are variable in shape, broadly lobed at the base of the plant, and slender and feathery higher on the flowering stems. You can easily grow it using the coriander seeds(which you get in the grocery shops.) If you grow them in your home then you would notice that once the plants mature they yield green coloured seeds. You can use them in cooking as Dhania Seeds. When the plant matures more then the seeds will get dried and will have woody appearance. You can keep these seeds and dry them and put them in jar. The plants do not last for more than one season, so you need to sow them each season.
Note: Sometimes the grocery shops sell coriander seeds which are slightly roasted. you can not use them for sowing.
The leaves are used for garnishing the dishes. The seeds are used in cooking and the powder derived from the seeds is also used in many Indian recipes. It provides a nice flavour and somewhat helps in thickening the gravy as well.
The Dhania Powder is used towards the end of the cooking of a dish.