Fasting, what is it?

What is fasting? It has something to do with all these topics: fasting, cleansing, no food, juice fast, juicing, eat less, purification, meditation, religious practice, digestion, solid foods, liquid food, breatharian. Are there good reasons to do fasting? There are many specifics on how to conduct the fasting period. But the general idea has to be comprehended first. It is all about taking a rest. It's almost like sleep. It is letting the digestive system take a rest, letting it sleep. This is very useful to do, every once in awhile. It is logical, because we have to operate our activities on a cycle. On then off then on again, repeat cycle. You can compare it to machines which we use so often in this modern age. As a reminder. But we are the original machine, the real, organic, flesh and blood machine.