The word "document" denotes any matter expressed or described upon any substance by means of letters, figures or marks, or by more than one of those means, intended to be used, or which may be used, as evidence of that matter.
Explanation 1: It is immaterial by what means or upon what substance, the letters, figures or marks are formed, or whether the evidence is intended for, or may be used in, a Court of Justice, or not.
Explanation 2: Whatever is expressed by means of letters, figures or marks as explained by mercantile or other usage, shall be deemed to be expressed by such letter, figure or marks within the meaning of this section, although the same may not be actually expressed.