classes of learning: [supervised](https://en.wikipedia.org/wiki/Supervised_learning), [unsupervised](https://en.wikipedia.org/wiki/Unsupervised_learning), and [reinforcement](https://en.wikipedia.org/wiki/Reinforcement_learning).  

We will focus on **supervised learning** and will begin with Ordinary Least Squares (OLS) and Lasso regression, followed by tree-based and ensemble classification methods. 

The syntax for supervised machine learning algorithms can be thought of like this:  

`\(y\)` ~ `\(x_{1}\