03. Intro to Probability Distributions Part Two
Intro To Probability Distribution 2
What is a Probability Distribution?
Probability distributions allow you to represent the probability of an event using a mathematical equation. Like any mathematical equation:
- probability distributions can be visualized using a graph especially in 2-dimensional cases.
- probability distributions can be worked with using algebra, linear algebra and calculus.
These distributions make it much easier to understand and summarize the probability of a system whether that system be a coin flip experiment or the location of a self-driving car.
Types of Probability Distributions
Probability distributions are really helpful for understanding the probability of a system.
Looking at the big pictures, there are two types of probability distributions:
- discrete probability distributions
- continuous probability distributions
Before we get into the details about what discrete and continuous mean, take a look at these two visualizations below. The first image shows a discrete probability distribution and the second a continuous probability distribution. What is similar and what is different about each visualization?

Discrete Distribution (left) and Continuous Distribution (Right)
Discrete and continuous distributions
SOLUTION:
- The x-axis represents the main variable of interest for both visualizations.
- In the discrete visualization, the x-axis variable can only take on certain values such as 1, 2 or 3.
- In the continuous visualization, the x-axis variable can take on any real number value from -infinity to +infinity.
- For the discrete visualization, the y-axis represents the probability of an event occurring (hint: what does the y-axis label say?).