| Horde_Lock | The Horde_Lock class provides an API to create, store, check and expire locks based on a given resource URI. |
| Horde_Lock_Exception | Exception handler for the Horde_Lock package. |
| Horde_Lock_Mongo | Lock storage in a MongoDB database. |
| Horde_Lock_Null | A null driver for Horde_Lock. |
| Horde_Lock_Sql | The Horde_Lock_Sql driver implements a storage backend for the Horde_Lock API. |