3.1.1.1 Naming

Each key MUST have a Base Name that consists of one or more Unicode characters. The Base Name of a key MUST NOT include the "\" character.

Each key contains zero or more child subkeys. The Base Name of each subkey that has the same parent key MUST be unique. A key that is a child key, either directly of a given parent key or through multiple parent-child key relationships is a subkey of its ancestor keys. A key MUST have at most one parent key and MUST NOT be an ancestor of itself.

Each subkey also MUST have an index that is associated with it. Indices MUST be zero-based. If a key has N subkeys that are associated with it, the subkeys have indices ranging from 0 to (N–1). However, the ordering of the subkeys and its associated indices is implementation-specific.