It is supposed that water has memory. Where the water has been is imparted onto the water and when the water is frozen its condition can be observed. If the water is treated well it is more crystalline while if the water is treated badly it is not.
This can be similar to a dent in a car, the dent in a car from an accident is a memory of the incident, in a similar way liquids may also have a memory of their past.
Why is this important?
This is important because the human immune system relies on information to do what it does. We use virus to inform the immune system of bio markers for cancers, bad cells and disease so that the immune system can act.
It is suggested that if water has memory then it is also programmable. That is we can put information in the water and have the person drink it in the hope that if communicates its memory with the cell or the immune system in a way that informs or helps the body.
If this can work or how it can work is yet to be known. A way to find out is training or programming water versus its effects on plants or bacteria if any.