1. In Memory Grids break problems into parts that can be solved using multiple resources on a network, using main memory instead of disk for faster file I/O.
2. In Memory Compute Grids allow computation tasks to be split and executed in parallel across grid nodes, while In Memory Data Grids provide applications with the ability to keep frequently accessed data in memory across multiple JVMs for high availability and low latency access.
3. Reference architectures show how In Memory Grids distribute data, computation tasks, and resources across a cluster for real-time processing of large datasets.