The oreeginal Semitic letter mey hae been inspired bi an Egyptian hieroglyph for tp, ""head"". It wis uised for /r/ bi Semites acause in thair leid, the wird for ""heid"" wis rêš (an aa the name o the letter). It developed intae Greek 'Ρ' ῥῶ (rhô) an Latin R. It is likely that some Etruscan an Wastren Greek fairms o the letter addit the extra stroke tae distinguish it frae a later fairm o the letter P.