Shatkarma also known as Shatkriya, refers to the Yogic

Yoga

Yoga is a physical, mental, and spiritual discipline, originating in ancient India. The goal of yoga, or of the person practicing yoga, is the attainment of a state of perfect spiritual insight and tranquility while meditating on Supersoul...

 practices involving purification of the body.

Shatkarm' is a compound word consisting of two components: shat meaning 'six' and karma meaning 'art' or 'process'. The word kriya or karma is used in Hatha Yoga

Hatha yoga

Hatha yoga , also called hatha vidya , is a system of yoga introduced by Yogi Swatmarama, a Hindu sage of 15th century India, and compiler of the Hatha Yoga Pradipika....

 in a special technical sense regarding the techniques of cleaning. These practices, outlined by Yogi Swatmarama

Yogi Swatmarama

Yogi Swatmarama was a 15th and 16th century yogic sage in India. He is best known for compiling the Hatha Yoga Pradipika, which introduced the system of Hatha Yoga...

 in the Haṭha Yoga Pradīpikā

Hatha Yoga Pradipika

The Hatha Yoga Pradipika is a classic Sanskrit manual on hatha yoga, written by Svami Svatmarama, a disciple of Swami Gorakhnath. Said to be the oldest surviving text on the hatha yoga, it is one of the three classic texts of hatha yoga, the other two being the Gheranda Samhita and the Shiva...

, are:

• Netī
  Neti (Hatha Yoga)
  Neti is an important part of Shatkarma , the yogic system of body cleansing techniques. It is intended mainly to the cleaning of the air passageways in the head...
  
  , nasal cleaning.
• Dhautī
  Dhauti (Hatha Yoga)
  Dhauti is an important part of the Shatkarma ,the yogic system of body cleansing techniques. It is intended mainly to the cleaning of the digestive tract in its full length but it affects also the respiratory tract, external ears and eyes. According to Gheranda Samhita, it is divided into four...
  
  , cleaning of the digestive tract.
• Naulī
  Nauli
  Nauli is one of the Kriyas or Shatkarma from Yoga. The exercise is to serve the cleaning of the abdominal region - digesting organs, small intestine and is based on a massage of the internal belly organs by a circular movement of the abdominal muscles.Nauli is an exercise of the classical Hatha...
  
  , abdominal massage.
• Basti
  Basti (Hatha Yoga)
  Basti is an important part of Shatkarma , the yogic system of body cleansing techniques. It is intended mainly to the cleaning of the lower abdomen, especially the colon. Both the Hatha Yoga Pradipika and other sources usually attribute to it many beneficial effects...
  
  , colon cleaning.
• Kapālabhātī
  Kapalabhati (Hatha Yoga)
  Kapalabhati , is an important part of Shatkarma , the yogic system of body cleansing techniques.The word kapalbhati is made up of two words, kapal meaning skull and bhati means shining, illuminating...
  
  , purification and vitalisation of the frontal lobes.
• Trāṭaka
  Trataka
  Trataka is the practice of staring at some external object. It is used in yoga as a way of developing concentration, strengthening the eyes, and stimulating the Ajna chakra....
  
  , blinkless gazing.

More details

• Netī refers to nasal wash. This is the practice of using a neti pot
  Neti pot
  A neti pot is a device used for irrigating the nasal passages. Typically it has a spout attached near the bottom, sometimes with a handle on the opposite side.-Function:...
  
   to cleanse the nasal passages. A basic neti wash consists of purified water and non-iodized salt, to create a gentle saline solution. A demonstration of this practice is available through the website of the Himalayan Institute.

• Kapālabhātī refers to skull polishing, and is a pranayama
  Pranayama
  Pranayama is a Sanskrit word meaning "extension of the prana or breath" or more accurately, "extension of the life force". The word is composed of two Sanskrit words, Prāna, life force, or vital energy, particularly, the breath, and "āyāma", to extend, draw out, restrain, or...
  
   (breathing) practice intended to energize and balance the nadis, and the chakras. Specifically, it is a sharp, short outbreath, followed by a relaxation of the core that allows the body to inhale on its own.

• Naulī
  Nauli
  Nauli is one of the Kriyas or Shatkarma from Yoga. The exercise is to serve the cleaning of the abdominal region - digesting organs, small intestine and is based on a massage of the internal belly organs by a circular movement of the abdominal muscles.Nauli is an exercise of the classical Hatha...
  
   refers to intestinal cleansing. The practitioner stands with the feet about hip width apart, hands on knees, and body at about a 45 degree angle. The core is rotated internally by moving the abdominal muscles alternately in a clock-wise, then counterclock-wise direction.