# Core Concepts

Before diving into the API, it's helpful to understand the basic objects and terminology used in the Blueink ecosystem.

## Bundle (Envelope)
A **Bundle** is the primary container for a signing workflow. It represents a single request for signatures and can contain:
- One or more **Documents** to be signed.
- One or more **Packets** (signers).
- Validation rules and metadata.

## Packet (Signer)
A **Packet** represents an individual signer within a Bundle. Each Packet contains:
- The signer's contact information (name, email, phone).
- The signer's assigned role in the documents.
- A unique signing link.

## Person (Contact)
A **Person** is a reusable contact record in your Blueink account. While Packets are specific to a Bundle, Persons are long-lived and can be referenced across multiple Bundles to avoid re-entering signer details.

## Template
A **Template** is a reusable document definition that includes pre-placed signature and form fields. Using templates allows you to automate repetitive signing tasks by simply mapping signers to pre-defined roles.

- **Document Template**: A single document with fields.
- **Envelope Template**: A collection of document templates and signer roles ready to be launched as a Bundle.