There are several styles of indention employed in type composition. These are known as (1) regular paragraph, (2) hanging indention, (3) half-diamond indention or inverted pyramid indention, with its variation of lozenge-shape formation, (4) squared indention, and (5) diagonal indention.

Hanging indention is where the first line of a paragraph begins flush and the second and succeeding lines are indented, as in this paragraph. It is a common form in catalogs, tabular work, and also in poetry.

It is often advisable to indent lines at both ends, to make several short lines instead of one or two long lines. In cases of this kind the first line is not indented more than the others, as shown in this paragraph. Squared indention is used for short paragraphs in advertising matter, bits of minor display, and miscellaneous composition.

Another manner of indenting lines, somewhat rare in this country but common in Europe, is termed French motto indention. This is usually made with small types, the paragraph being set in squared-up fashion at the right side of the page, within the measure.

An indention should be enough to indicate the paragraph clearly, yet not be so wide as to make it a conspicuous white spot on the page. Its purpose is to show the reader a change of subject or a minor subdivision of the matter. The amount of indention necessary to attain this will vary in different forms of composition, and therefore only general rules can be given.

The usual indention of paragraphs in plain reading matter is an em quad at the beginning of the first line. If the lines are more than average length the indention may be increased to one and a half ems, two ems, or more. Indentions of over two ems, however, are seldom allowable in ordinary reading matter like books and periodicals.

Wide indentions should not be made in narrow measures; nor should indistinct, insignificant indentions be made in broad measures.

Paragraphs set in 10-point or 12-point type in measures from 15 to 20picas wide are sufficiently indented by the em quad, while 6-point type in the same measure should be indented with a two-em quad.

Wide-leaded, open matter will call for a little more paragraph indention, as a rule, than is given to thin-spaced solid-line paragraphs. In pamphlets, circulars, advertisements, and job work, where wide leading and broken lines of a miscellaneous character are frequent, paragraph indentions may be wider than in book pages. On the other hand, in composition of this kind where other means of showing the commencement of a subject are used, indentions are omitted and the paragraphs begun flush at the margin.

The indention of paragraphs should be uniform throughout any single book or job. It is rare that more than two different widths of indention are needed to give a clear idea of the classification of any group of subjects. A variety of indentions on the same page is confusing and often spoils the orderly arrangement of the matter which the copy writer sought to obtain. Even where there are several sizes of type on the page, if the paragraphs are the same width, the indentions should be alike.

A common defect that is made conspicuous when wide indentions are made in paragraphs following each other is the occurrence of a single short word or syllable in the last line of a paragraph, as shown in this example:

This constitutes a “bad break” and should be avoided either by thin-spacing the last two or three lines of the paragraph to take the short word back and save the line, or by over-running the lines with wider spaces to bring more words to the last line. The choice of these expedients will depend upon the openness or closeness of the composition, in many cases upon the make-up of the page. If a line can be saved, take the solitary word back; if the line is needed, space out the preceding lines, provided it may be done without making bad spacing.