Content type defines the actual format of the data that flows through system. Logic Apps engine can process multiple content types, such as JSON, XML, Flat Files, and binary data. There are some natively supported content type for Logic App workflow engines such as JSON, Text, and XML, and other requires casting from one format to another.
The Content-Type header is used to specify the nature of the data in the body of an entity, by giving type and subtype identifiers, and by providing auxiliary information that may be required for certain types. When a client posts a request to the server and specifies the content type, it makes easy for the server to understand the data and parse it.
These are the basic Content-Type, we use within a Logic App.
text/plain
application/json
application/xml