In typesetting by hand compositing, a sort, otherwise referred to as a type, is a block representing a specific letter, digit or other symbolcast from a matrixmould and made with other sorts bearing additional symbols into lines of type to make up a forme from which a page is printed.
Nesbitt, Alexander The History and Technique of Lettering (c) 1957, Dover Publications, Inc.ISBN0-486-20427-8, Library of Congress Catalogue Card Number: 57-13116. The Dover edition is an abridged and corrected republication of the work originally published in 1950 by Prentice-Hall, Inc. under the title Lettering: The History and Technique of Lettering as Design.