Before we dive into the Airbnb dataset and our findings, let's do an in-depth review of the K-Means clustering algorithm. An unsupervised learner receives unlabeled training data and makes predictions for unseen points. Clustering analysis falls under unsupervised learning. A cluster is a collection of data objects that are similar (or related) to one another within the same group, or dissimilar (or unrelated) to the objects in other groups. "Good" clusters will have the following: high intra-class similarity (cohesiveness within clusters) and low inter-class similarity (distinctive between clusters). The K-Means algorithm is common a type of clustering analysis.