In WHMCS, "Core Statuses" refer to the predefined system statuses that are fundamental to the operation of the platform. These statuses are used to manage various aspects of client accounts, orders, services, and more. Here are some of the core statuses commonly used in WHMCS:

1. Active: This status indicates that a service or product is currently active and operational.

2. Pending: This status is typically used to indicate that an action is pending, such as pending activation or payment.

3. Suspended: This status signifies that a service or product has been temporarily suspended, often due to non-payment or other issues.

4. Canceled: An order or service with this status has been officially canceled and is no longer active.

5. Terminated: This status indicates that a service or product has been permanently terminated or deleted.

6. Fraud: If an order or transaction is suspected to be fraudulent, it may be assigned this status, indicating that further action or verification is required.

7. Expired: This status is used when a service or subscription has reached the end of its billing cycle and has not been renewed.

8. Refunded: If a refund has been processed for an order or service, it will be marked with this status.

9. Completed: This status is used when all aspects of an order or service have been successfully completed and no further action is required.

10. Pending Transfer: For domain orders, this status indicates that the domain transfer process is in progress.

11. Pending Registration: For domain orders, this status indicates that the domain registration process is in progress.

12. Pending Transfer Approval: This status is specifically for domain transfers and indicates that approval is required from the domain owner.

13. Pending Hold: This status may be used to temporarily hold a service or order, often due to billing or administrative reasons.

These are some of the core statuses commonly used in WHMCS. Keep in mind that the specific list of statuses and their meanings may vary based on your WHMCS setup, any customizations you've made, and the services you offer. Familiarizing yourself with these core statuses is crucial for effectively managing client accounts, orders, and services within WHMCS.