[Copernicus]

If thats the way you would explain it to a child, I'd hate to be your kid!

The normal curve is the bell shaped curve. The higher the curve and closer in the tails are, the lower the standard deviation is. The squatter the curve and more spread out the tails are, the higher the standard deviation is.

The probability of your results lying outside different points in the tails for a given standard deviation are given by z tables.