Classifiers are algorithms used in machine learning and artificial intelligence to categorize data into predefined classes or groups. They analyze input data, such as images or text, and assign labels based on learned patterns from training data. Common examples of classifiers include decision trees, support vector machines, and neural networks. In practical applications, classifiers are used in various fields, such as spam detection in emails, image recognition in photos, and sentiment analysis in social media. By effectively sorting data, classifiers help automate decision-making processes and improve the efficiency of data management systems.