Normal/Gaussian Distribution: Bell Curve




https://mathworld.wolfram.com/NormalDistribution.html
Univariate Normal Distribution:


BiVariate Normal/Gaussian Distribution



https://www.probabilitycourse.com/chapter5/5_3_2_bivariate_normal_dist.php
Multi Variate Random variable

https://en.wikipedia.org/wiki/Multivariate_normal_distribution