Mammoth is designed to convert .docx documents, such as those created by
Microsoft Word, and convert them to HTML. Mammoth aims to produce simple
and clean HTML by using semantic information in the document, and
ignoring other details. For instance, Mammoth converts any paragraph with the
style Heading1 to h1 elements, rather than attempting to exactly copy the
styling (font, text size, colour, etc.) of the heading. This allows you to paste
from Word documents without the usual mess.