# Writing Data

- [NPM SDK](/for-builders/index-1/npm-sdk.md)
- [Installation](/for-builders/index-1/npm-sdk/installation.md)
- [Usage](/for-builders/index-1/npm-sdk/usage.md)
- [Schemas](/for-builders/index-1/npm-sdk/usage/schemas.md)
- [Attestations](/for-builders/index-1/npm-sdk/usage/attestations.md)
- [Examples](/for-builders/index-1/npm-sdk/examples.md)
- [Changelog](/for-builders/index-1/npm-sdk/changelog.md)
- [Smart Contract](/for-builders/index-1/index.md)
- [EVM](/for-builders/index-1/index/index.md)
- [Interfaces](/for-builders/index-1/index/index/index.md)
- [ISP](/for-builders/index-1/index/index/index/isp.md): Version 1.0.0-beta18
- [ISPHook](/for-builders/index-1/index/index/index/isphook.md): The hook is called for every attestation or revocation if the schema used specifies a hook.
- [IVersionable](/for-builders/index-1/index/index/index/iversionable.md): This interface helps contracts to keep track of their versioning.
- [Data Models](/for-builders/index-1/index/index/index-1.md)
- [Schema](/for-builders/index-1/index/index/index-1/schema.md)
- [Attestation](/for-builders/index-1/index/index/index-1/attestation.md)
- [DataLocation](/for-builders/index-1/index/index/index-1/datalocation.md)
