We encounter them in daily life yet couldn't comprehend them to use it for our benefit, where as big organization use it for their advantage (amazon trying to predict what its user might be interested - example of regression) . One problem is, these subjects are explained by mathematicians for mathematicians, this article from http://www.betterexplained,com explains that in simple language

http://betterexplained.com/articles/a-brief-introduction-to-probability-statistics/