What Determines a Substance's Classification as Crystalline, Amorphous, or Both?

[dido28]

i read on a book that the matter can be classified as crystalline substances , amorphous substances or both of them depending on the % of packed crystalline part .
please can you explain me what does it mean

 

[chemisttree]

Analagous to an assertion that all substances are wet, dry or both depending upon the % of the dry part.