ing ▁System ▁class ifies ▁af ro - text ured ▁hair ▁as ▁' type ▁ 4 ' ▁( there ▁are ▁other ▁types ▁of ▁hair , ▁defined ▁as ▁type ▁ 1 ▁for ▁straight ▁hair , ▁type ▁ 2 ▁for ▁w avy , ▁and ▁type ▁ 3 ▁for ▁cur ly , ▁with ▁the ▁letters ▁A , ▁B , ▁and ▁C ▁used ▁as ▁indic ators ▁of ▁the ▁degree ▁of ▁co il ▁variation ▁in ▁each ▁type ), ▁with ▁the ▁sub category ▁of ▁type ▁ 4 C ▁being ▁most ▁exempl ary ▁of ▁the ▁af ro - text ured ▁hair . ▁However , ▁af ro - text ured ▁hair ▁is ▁often ▁difficult ▁to ▁categor ize ▁because ▁of ▁the ▁many ▁different ▁variations ▁among ▁individuals . ▁Those ▁variations ▁include ▁pattern ▁( main ly ▁tight ▁co ils ), ▁pattern ▁size ▁( watch ▁spring ▁to ▁ch alk ), ▁density ▁( s parse ▁to ▁dense ), ▁str and ▁diameter ▁( f ine , ▁medium , ▁co arse ), ▁and ▁feel ▁( cot ton y , ▁w ool ly , ▁sp ong y ). ▁ ▁The ▁chart ▁below ▁is ▁the ▁most ▁commonly ▁used ▁chart ▁to ▁help ▁determine ▁hair ▁types : ▁ ▁Str ucture ▁ ▁D ifferent ▁eth nic ▁groups ▁have ▁observable ▁differences ▁in ▁the ▁structure , ▁density , ▁and ▁growth ▁rate ▁of ▁hair . ▁With ▁regard ▁to ▁structure , ▁all ▁human ▁hair ▁has ▁the ▁same ▁basic ▁chemical ▁composition ▁in ▁terms ▁of ▁ker atin ▁protein ▁content . ▁Fran bourg ▁et ▁al . ▁have ▁found ▁that ▁Black ▁hair ▁may ▁differ ▁in ▁the ▁distribution ▁of ▁lip ids ▁throughout ▁the