[edit] General preferences
Four main preferences exist today:
Some authors believe that text using double-spaces between sentences is more readable than text written with only one space after the period.[13][28][29][30]
Some authors believe that proportionally spaced fonts have made double-spacing redundant, and that it should only be used in a monospaced (nonproportional) font.[31] The argument here is that double-spacing was an attempt in a monospaced font to create the effect of proportional fonts' spaces, and that the ready availability now of proportional fonts renders a double-space redundant. However, the width of spacing in a proportional font width is nearly always narrower than an em space. This argument is supported by renowned typographer, Ben Worrall. When questioned about the practice of double spacing, he replied: "It makes me physically sick."[32]
Some authors (particularly professional designers or typographers) believe that double-spacing creates an unappealing appearance.[18][33][34]
Some authors believe best practice is dependent on the particular typeface being used.[35]