The clipboard only really understands raw bytes. It does not
inherently know how whether those bytes are text or a picture or a table or something else.
The java.awt.datatransfer.DataFlavor class uses
MIME types and subtypes to identify the kind of data stored in the clipboard.
MIME, the Multipurpose Internet Mail Extensions, is an Internet standard defined in RFCs 2045 through 2049 for transferring multimedia, binary data through 7-bit ASCII email. RFC 2046 in particular specifies the MIME type system and defines the base set of media types. New MIME types are registoered with and approved by the Internet Assigned Numbers Authority (IANA). The current list of standardized types is available from ftp://ftp.isi.edu/in-notes/iana/assignments/media-types/media-types.
A MIME type has a type and a subtype. For example, text/plain, application/x-java-serialized-object, or image/gif. There are five defined types: text, image, audio, video, multipart, message, model, and application. The first seven are self-explanatory. The last is used for arbitrary binary data. Subtypes that begin with an x such as "x-java-serialized-object" are unofficial, application specific extensions. Two different programs are not guaranteed to interpret the same x type as representing the same kind of data.