In IMS DB (Information Management System Database), there are primarily two types of databases :

Full Function Database (FFD) : Full Function Databases are traditional IMS databases that support the full range of IMS features, including hierarchical data organization, complex data relationships, and sophisticated transaction processing capabilities. FFDs are suitable for applications that require extensive data manipulation, hierarchical data modeling, and high-performance transaction processing. They offer robust features for data integrity, concurrency control, and recovery.

Fast Path Database (FPD) : Fast Path Databases are optimized for high-speed transaction processing and are designed to handle large volumes of online transactions with minimal response times. FPDs utilize specialized data structures and access methods to expedite data retrieval and update operations, enabling rapid access to frequently accessed data. They are well-suited for online transaction processing (OLTP) applications such as banking, reservation systems, and telecommunications, where quick response times are critical.

These two types of databases cater to different application requirements and performance objectives. Full Function Databases provide comprehensive functionality for managing complex data structures and transaction processing logic, while Fast Path Databases prioritize speed and efficiency for high-volume transaction environments. Organizations choose between FFDs and FPDs based on their specific application needs, performance goals, and scalability requirements.