Classification Types:
Classification refers to the process of categorizing items or data into groups based on certain similarities or characteristics. In this case, classification is of four kinds.

Explanation:
- Binary Classification: Binary classification involves categorizing items into two groups or classes. For example, classifying emails as spam or not spam.
- Multi-class Classification: Multi-class classification involves categorizing items into more than two classes. For example, classifying fruits into categories like apples, oranges, and bananas.
- Multi-label Classification: Multi-label classification assigns multiple labels to an item. For instance, a movie can be classified under genres like action, comedy, and drama simultaneously.
- Hierarchical Classification: Hierarchical classification involves organizing items into a tree-like structure of categories. For instance, classifying animals into mammals, birds, reptiles, etc., and further subcategories within each group.
Therefore, the statement that classification is of four kinds is accurate as it encompasses different approaches to organizing and categorizing data or items based on specific criteria.