Cord Blood Stem Cells

I am from Kolkata can be explained the concept of cord blood stem cell banking? What's this? How? How important it is? What is the cost involved?
Also please suggest which company is best for the stem cell bank in Kolkata.

When a baby is born, blood from the umbilical cord and placenta is readily available which is the richest source of stem cells.It may be kept by a consulting firm like Reliance for 20 years and payment of certain rights it can still be preserved for a number of years.At present the role of these cells is limited to say in a spinal cord injury or heart disease or stroke, but much research is at an advanced stage where scientists will be able to creat a new body as a replacement for the damaged one.The cord blood stem cells taken at time of delivery of the baby are most appropriate for the treatment of all family members.At blood relative This cost is approxi.Rs.70 India, 000 / =. I hope it helps.