The answer to the question is not straight forward. It purely depends on the situation. Gift deed of immovable property or lease of immovable property are to be registered.
Along with this some other instruments like a Will or a testamentary instrument (any document that creates, extinguishes, or transfers an interest in, or right to, an asset or property. Also called testamentary document). are to be registered.
For Example: Sale, mortgage, partition, release, settlement of immovable property
Registration of a document provides the legal power to exercise on the registered property by law.