# Document¶

Document is the basic data type that Jina operates with text, picture, video, audio, image or 3D mesh: They are all Documents in Jina.

DocumentArray is a sequence container of Documents. It is the first-class citizen of Executor, serving as the Executor’s input and output.

DocumentArrayMemmap is an on-disk sequence container of Documents. It shares almost the same interface as DocumentArray but with much smaller memory footprint.

Hint

You could say Document is to Jina is what np.float is to Numpy, and DocumentArray is similar to np.ndarray.