This document discusses caching strategies for web applications and ORM caching. It begins with an overview of why caching is important and how it can speed up applications based on Amdahl's law. It then discusses two levels of ORM caching - first level session caching and second level caching using various cache providers like EhCache. The caching strategies covered are read-only, read-write, transactional and nonstrict read-write. Memory, disk, clustered and server caching types are also mentioned.