# NIPs NIPs stand for **Nostr Implementation Possibilities**. They exist to document what MUST, what SHOULD and what MAY be implemented by [Nostr](https://github.com/fiatjaf/nostr)-compatible _relay_ and _client_ software. - [NIP-01: Basic protocol flow description](01.md) - [NIP-02: Contact List and Petnames](02.md) - [NIP-03: OpenTimestamps Attestations for Events](03.md) - [NIP-04: Encrypted Direct Message](04.md) - [NIP-05: Mapping Nostr keys to DNS-based internet identifiers](05.md) - [NIP-06: Basic key derivation from mnemonic seed phrase](06.md) - [NIP-08: Handling Mentions](08.md) - [NIP-09: Event Deletion](09.md) - [NIP-11: Relay Information Document](11.md) - [NIP-12: Generic Tag Queries](12.md) ## Event Kinds | kind | description | NIP | |------|---------------------------|-----| | 0 | Metadata | 5 | | 1 | Text | 1 | | 3 | Contacts | 2 | | 4 | Encrypted Direct Messages | 4 | | 5 | Event Deletion | 9 | Please update this list when proposing NIPs introducing new event kinds.