A NoSQL database is designed to store and retrieve unstructured data, distinguishing it from traditional relational databases. NoSQL databases are capable of handling large volumes of varied data types, such as text, images, or videos, without a predefined schema. This flexibility allows developers to manage Big Data and adapt to changing data structures efficiently. Common types of NoSQL databases include document stores, key-value stores, and column-family stores. Their scalable architecture makes them a popular choice for modern applications that demand high performance and rapid data retrieval.