Data is usually distributed in different ways with a bias to the left or to the right or it can all be jumbled up.
However, there are chances that data is distributed around a central value without any bias to the left or right and reaches normal distribution in the form of a bell-shaped curve.
Figure: Normal distribution in a bell curve
The random variables are distributed in the form of a symmetrical, bell-shaped curve.
Properties of Normal Distribution are as follows;
1. Unimodal -one mode
2. Symmetrical -left and right halves are mirror images
3. Bell-shaped -maximum height (mode) at the mean
4. Mean, Mode, and Median are all located in the center