A ligature is a single character that combines two characters. The most common ligatures, appearing in almost all typefaces on the Macintosh are fi and fl. If you look closely, you can see the difference in the example below.
Separate characters: fi fl
Ligatures: fi fl
Using ligatures is considered proper typesetting, but if you are not a graphic designer or typesetter, you might not care about ligatures and might even want to avoid them. There is a disadvantage to using ligatures; spell checking utilities don’t recognize them as the two characters they represent, so when you spell-check a document, each word with a ligature will be flagged as an incorrectly spelled word. You can ignore the warning of course, but this makes spell-checking take a little longer. Ligatures are not Web-compatible characters, and therefore should not be set, or even removed if your text is going to be converted to HTML.
Text Cleaner has the “fi and fl ligatures” cleaning option turned off by default. Check the box if you want to create or remove ligatures in your cleaned documents and select the appropriate choice from the pop-up menu. Your change is saved automatically.
