If you have been working with the Salesforce platform, you will already be aware that the Metadata API format is used for the deployment of code and configuration from one Salesforce instance to another.

Salesforce DX has a different folder format than the Metadata API format. The Salesforce DX force Metadata API commands allow you to convert the Metadata API file format into the Salesforce DX format for development, and also provides a command to deploy file representations into your production Orgs or package Orgs for ISV applications.