 With the fabric shortage still in place and in an endeavour to resurrect swimwear sales , two French designers – Jacques Heim and Louis Réard – almost simultaneously launched their new two @-@ piece swimsuit ranges in 1946 . Heim launched his two @-@ piece swimsuit in Paris which he called the atome , after the smallest known particle of matter . He advertised the Atome as the world 's " smallest bathing suit " . At about the same time , Louis Réard created a competing two @-@ piece swimsuit design , which he called the bikini . 
