What is a cumumlative distribution function?
Shows the distribution of probabilities under graph.
Integrating over a range gives us the probability within that range.
Let X be a random variable, discrete / continuous.
F(x) is the cumulative distribution function of the random variable X.
F(x) = Pr(X <= x)
Case 1: X is discrete
F(x) = sumof f(t), for ranges t<=x. = sumof Pr(X = t), for range t <= x.
It is a step function.