JTec beads defines several types of content to be stored in beads. Bead is not bound to distinct type of content, and may host different kinds to different times.
"Primitive" speaks for itself. It's just primitive content - like text or binary data. It is separated into text and binary content because text may be indexed or otherwise parsed and altered during rendering, while nothing can be done to binary content except deliver it verbatim.
Text content is basically just a wrapper for java.lang.String and can be of arbitrary length.
Binary content can be theoretically of arbitrary length, and is accesible as either as file, or ( for convenience ) as stream.