Japan Karate Do Hakua-Kai Matsubushi Dojo

Kumite is a method of training in which the offensive and defensive techniques learned in the kata are given pratical application.
The opponents are face to face.The importance of kata to kumite cannot be overemphasized.If techniques are used unnaturally or in a forced way,posture will break down.
And if the kata techniques become confused when applied,on improvement in kumite can be expected.In other words,improvement
in kumite depends directly on improvement in kata;the two go together like hand in glove.It is a mistake to emphasize one at the expense of the other.

This is a point to be careful about when practicing kumite.Since the word "kumite" refers to forms of sparring, it covers a vast range of activities. In traditional Shotokan karate, the first type of kumite for beginners is gohon kumite.
The defender steps back each time, blocking the attacks and performing a counterattack after the last block.This activity looks nothing like the jiyu kumite (or "free sparring") practiced by more advanced practitioners, which is far closer to how karate would look if used in a real fight, especially because it is not choreographed. Karate and other forms of martial arts have various other types of kumite (5-step, 3-step, 1-step, semi-free) which span this large range in styles of practice

         Types of Kumite
     >* Ippon kumite - one step sparring, typically used for self defense drills.
     * Sanbon kumite,Gohon kumite- three and five step sparring, typically used to develop speed, strength, and technique
     * Kiso kumite - structured sparring drawn from a kata
     * Jiyu kumite - free sparring

Sparring in Karate is called kumite (g). It literally means "meeting of hands." Kumite is practiced both as a sport and as self-defense training. Sport kumite in many international competition under the World Karate Federation is free or structured with light contact or semi contact and points are awarded by a referee. Sparring in armour (bogu kumite) allows full power techniques with some safety. In structured kumite (Yakusoku - prearranged),two participants perform a choreographed series of techniques with one striking while the other blocks. The form ends with one devastating technique .In free sparring (Jiyu Kumite), the two participants have a free choice of scoring techniques. The allowed techniques and contact level are primarily determined by sport or style organization policy, but might be modified according to the age, rank and sex of the participants. Depending upon style, take-downs, sweeps and in some rare cases even time-limited grappling on the ground are also allowed.Free sparring is performed in a marked or closed area. The bout runs for a fixed time (2 to 3 minutes.) The time can run continuously or be stopped for referee judgment. In light contact or semi contact kumite, points are awarded based on the criteria: good form, sporting attitude, vigorous application, awareness/zanshin, good timing and correct distance.
Reference :Wikipedia