19.5.2 \frenchspacing & \nonfrenchspacing

Synopsis, one of:


\frenchspacing causes LaTeX to make spacing after all punctuation, including periods, be the same as the space between words in the middle of a sentence. \nonfrenchspacing switches back to the default handling in which spacing after most punctuation stretches or shrinks differently than a word space (see \spacefactor).

In American English, the typesetting tradition is to adjust, typically increasing, the space after punctuation more than the space between words that are in the middle of a sentence. Declaring \frenchspacing (the command is inherited from plain TeX) switches to the tradition that all spaces are treated equally.

If your LaTeX document specifies the language being used, for example with the babel package, the necessary settings should be taken care of for you.

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