Ridge Regression, also known as Tikhonov regularization, is a type of linear regression that incorporates a regularization term. This regularization term discourages overly complex models which can lead to overfitting.
Logistic Regression is a supervised learning algorithm used for binary classification problems, i.e., when the output can be of two classes, like 'Yes' or 'No', '1' or '0'.
Linear regression is one of the most basic and widely used algorithms in the machine learning world. It's a statistical method that allows us to understand the relationship between two continuous variables.