The Data Vault category contains the following templates:

Data Vault – Hub. Generates unique business keys and writes them to a hub table along with the date the records are loaded.
Data Vault – Link. Creates relationships between hub or other link tables based on business keys and stores the connection in a link table.
Data Vault – Satellite. Generates a satellite table to store descriptive data such as context or history for either a hub or a link.

You can use the templates individually or use all three to help you structure your data. However, Data Vault components must be loaded sequentially. A link record must reference existing hub or link records, and a satellite record must reference its parent hub or link record.