Pic­ture a para­graph that starts at the bot­tom of one page and con­tin­ues at the top of the next. When only the last line of the para­graph ap­pears at the top of the sec­ond page, that line is called a widow. When only the first line of the para­graph ap­pears at the bot­tom of the first page, that line is called an or­phan.

Widow and or­phan con­trol pre­vents both. Or­phans are moved to the next page with the rest of the para­graph. To cure wid­ows, lines are moved from the bot­tom of one page to the top of the next. Thus, widow con­trol will fre­quently pro­duce ex­tra blank lines at the bot­tom of your pages.

Do you need widow and or­phan con­trol? Try it. See how it looks. In my own work, I ap­proach widow and or­phan con­trol the same way I ap­proach lig­a­tures—I only use it if wid­ows and or­phans are caus­ing a vis­i­ble prob­lem. Oth­er­wise, I find that the blank lines at the bot­tom of the page are more an­noy­ing than the wid­ows and orphans.