A soft or discretionary hyphen is a hyphen that is used at the author’s discretion to divide a word at the end of a line of text. It is also known as a non-breaking hyphen or a optional hyphen.
The use of soft or discretionary hyphens is common in typesetting and word processing, especially when justified text is used. Justified text is text that is aligned on both the left and right margins. In order to create this alignment, the word processor or typesetter must sometimes divide words at the end of a line of text. When this happens, a discretionary hyphen is inserted to tell the word processor or typesetter that the word can be divided at that point if necessary.
In books and publishing, discretionary hyphens are often used in words that appear on the cover or in the title of a book. This is because publishers want to avoid dividing words in a way that would make the title or cover look odd.
The use of soft hyphens can be helpful for readers who are trying to read a word that has been broken by a line break. By using a soft hyphen, the reader can more easily see where the word could be divided into two parts. This can make it easier to read the word, especially if the word is long or has a complex spelling.
The soft or discretionary hyphen is an important tool for publishers and book designers. It allows for greater control over the look and feel of a book, and can help to create a more uniform appearance. It also allows for greater flexibility in line breaks and page layouts. In short, the soft or discretionary hyphen is an important tool for creating a more polished and professional book.