Entities are distinct units that can be identified and categorized. They can be anything from a person, organization, or object to a concept or event. For example, a company like Apple is an entity, as is a person like Albert Einstein. Each entity has its own characteristics and attributes that help define it. In various fields, such as business, law, and computer science, understanding entities is crucial. In data management, entities are often represented in databases, where they can be organized and analyzed. This helps in making sense of complex information and relationships between different entities.