What is
Lassi is a popular, traditional, yogurt-based drink from the Indian Subcontinent and is popular in India. Lassi is a blend of yogurt, water, spices and sometimes, fruit
  
Kefir is fermented milk made by using kefir grains containing benefiicial yeast as well as probiotic bacteria found in the yogurt.
  
Origin
Europe, Greece, Italy
  
North Caucasus regions