Message types

WhatsApp allows businesses to send two primary types of messages -

1. Session Messages - These messages can be sent to the customer only within 24 hours of the last customer message and are not charged for by WhatsApp
2. Template Messages - These messages can be sent to the user proactively but the content of the message requires prior approval from WhatsApp

Session Messages

As these messages can only be sent in response to a customer message, session messages usually correspond to a customer care agent response or an automated bot response.
Session messages can be -

1. Text messages - Text upto 4096 characters and can contain links
2. Media messages - Audio, contact, document, image, location and video attachments are supported

Template Messages

Template messages require prior approval from WhatsApp. You can add them on the UI under Tools>Templates

Note - Template messages are charged on a per message basis by WhatsApp when sent out of the 24 hour window

Media templates can optionally contain headers and footers -

1. Headers can either be a document or image that can be passed dynamically in the API or a flow send node
2. Footers can only be text messages

Here is a sample media message with a image header and a text footer