What is the difference between wok and Kadai?

Kadai is neither a wok nor an Indian set pan. It has large, curved handles that have space between them so it looks like mini tawa placed upside down within the make up of kadai/iron kadai/non stick or stainless steel Kadii. The major difference from this gadget and its non-stick version (Kadhia) is that in non stick model you need to add oil for cooking but in kadai all you need is to add water. An important feature of kada, as explained earlier is that heat doesn't have to build up at the bottom and when covered with lid it also helps in preserving food for a longer time upto two hours rather than opening the lid for short duration which further provokes more pressure over frying pan resulting into momentary burning out of food from moisture inside.

Which type of Kadai is best for cooking?

Jhurka can be used for cooking but results in a lot of water and black scum, so it is not suitable for soaking dals or rice. Jhora (a thinnish Kadai) burns food from the bottom when added with the necessary amount of oil on top thus that temp isn't properly maintained till the time fried food comes near to the pressure bank as croquettes are supposed to have crunchy edges without being burnt even at higher heat.

What is a Kadai used for?

Kadai is one of the main cooking utensils used in palace kitchens among Indians. Different types can be found these days as jhora, dal v/s rice kadhia, stainless steel, and now even microwave safe versions are available at Snapdeal to take care of rich foodies too who want those high-end experience while they serve guests on a table loaded with homecooked foods prepared by mother's skillful hands.