| Horde_HashTable_Lock | Extension to base HashTable class by adding lock methods to prevent access from other PHP processes. |
| Horde_HashTable_Base | The Horde_HashTable class provides an API to interact with various hash table implementations. |
| Horde_HashTable_Exception | Base exception for the Horde_HashTable package. |
| Horde_HashTable_Memcache | Implementation of HashTable for a Memcache server. |
| Horde_HashTable_Memory | Implementation of HashTable within PHP memory. |
| Horde_HashTable_Null | Implementation of HashTable that stores nothing. |
| Horde_HashTable_Predis | Implementation of HashTable for a Redis server (using the Predis library). |
| Horde_HashTable_Vfs | Implementation of HashTable for a VFS backend. |