▁ ▁And ▁so ▁out ▁of ▁the ▁various ▁v av ▁variants ▁in ▁the ▁Mediter rane an ▁world , ▁the ▁letter ▁F ▁entered ▁the ▁Roman ▁alphabet ▁attached ▁to ▁a ▁sound ▁which ▁its ▁ante ced ents ▁in ▁Greek ▁and ▁E tr us can ▁did ▁not ▁have . ▁The ▁Roman ▁alphabet ▁forms ▁the ▁basis ▁of ▁the ▁alphabet ▁used ▁today ▁for ▁English ▁and ▁many ▁other ▁languages . ▁ ▁The ▁lower case ▁' f ' ▁is ▁not ▁related ▁to ▁the ▁vis ually ▁similar ▁long ▁s , ▁' ſ ' ▁( or ▁med ial ▁s ). ▁The ▁use ▁of ▁the ▁long ▁s ▁largely ▁died ▁out ▁by ▁the ▁beginning ▁of ▁the ▁ 1 9 th ▁century , ▁mostly ▁to ▁prevent ▁confusion ▁with ▁' f ' ▁when ▁using ▁a ▁short ▁mid - bar ▁( see ▁more ▁at : ▁S ). ▁ ▁Use ▁in ▁writing ▁systems ▁ ▁English ▁ ▁In ▁the ▁English ▁writing ▁system ▁ ▁is ▁used ▁to ▁represent ▁the ▁sound ▁, ▁the ▁vo ic eless ▁lab iod ental ▁fr ic ative . ▁It ▁is ▁often ▁double d ▁at ▁the ▁end ▁of ▁words . ▁Exception ally , ▁it ▁represents ▁the ▁vo iced ▁lab iod ental ▁fr ic ative ▁ ▁in ▁the ▁common ▁word ▁" of ". ▁F ▁is ▁the ▁tw elf th ▁least ▁frequently ▁used ▁letter ▁in ▁the ▁English ▁language ▁( after ▁C , ▁G , ▁Y , ▁P , ▁B , ▁V , ▁K , ▁J , ▁X , ▁Q , ▁and ▁Z ), ▁with ▁a ▁frequency ▁of ▁about ▁ 2 . 2 3 % ▁in ▁words . ▁ ▁Other ▁languages ▁In