The Postmark API is a cloud-based email service that allows developers to send and track the status of emails using Python. To use the Postmark API, developers need to create an authorization token and add it as a header in their REST requests. The API requires a minimum of sender information, recipient information, subject, and HTML body to be included in the request. The `requests` library is used to send the email and get the response from the Postmark API, which can be converted to JSON using the `json` library. Once an email is sent, developers can use the MessageID to check the status of the email by polling the Postmark API with a GET request. This allows developers to track the status of emails, including errors and delivery attempts, and provides valuable information for debugging and support purposes.