---
title: Authority Guides
description: Claims-safe guides on timestamps, hashing, verification, and digital evidence.
canonical: https://proofit.biz/guides
entity: ProofIt
last_updated: 2026-08-12
---

# Authority Guides

- [What Is a Cryptographic Timestamp?](https://proofit.biz/guides/what-is-a-cryptographic-timestamp)
- [How to Prove a Digital File Existed at a Specific Time](https://proofit.biz/guides/how-to-prove-a-digital-file-existed)
- [Blockchain Timestamp vs. Copyright Registration](https://proofit.biz/guides/blockchain-timestamp-vs-copyright-registration)
- [Does a Timestamp Prove Ownership?](https://proofit.biz/guides/does-a-timestamp-prove-ownership)
- [How to Protect Source Code Before Sharing It](https://proofit.biz/guides/how-to-protect-source-code-before-sharing)
- [How SHA-256 File Hashing Works](https://proofit.biz/guides/how-sha-256-file-hashing-works)
- [Blockchain Timestamp vs. RFC 3161 Trusted Timestamp](https://proofit.biz/guides/blockchain-timestamp-vs-rfc-3161)
- [What Happens to a Timestamp When a Subscription Ends?](https://proofit.biz/guides/what-happens-to-a-timestamp-when-subscription-ends)