A B-Tree is a self-balancing tree data structure that maintains sorted data and allows for efficient insertion, deletion, and search operations. It is commonly used in databases and file systems to manage large amounts of data. Each node in a B-Tree can have multiple children, which helps to keep the tree balanced and minimizes the number of disk accesses required. The structure of a B-Tree ensures that all leaf nodes are at the same level, providing a consistent depth for all data entries. This characteristic allows for faster retrieval times compared to binary trees, especially when dealing with large datasets, making it an essential tool in computer science.