This document provides an overview of data mining techniques designed for imbalanced datasets. It discusses how imbalanced datasets, where one class is greatly underrepresented compared to others, pose challenges for machine learning algorithms. Several approaches have been proposed to address this issue, including sampling methods like oversampling the minority class and undersampling the majority class, as well as cost-sensitive methods that assign higher misclassification costs. The document reviews common sampling strategies used for imbalanced datasets, such as SMOTE, and cost-sensitive approaches involving cost matrices and cost curves. Overall, it examines how various sampling and cost-based methods can help improve classification of imbalanced datasets in fields such as medical diagnosis and text classification.