problems are many and various and need to be solved by human to make his life easier . Scientist didn’t stop to find these solutions or trying to do that , in which scientist Molodtsov in 1999 , defined ( the soft set ) which was regarded quality change and important mathematic tool , to solve these problems that it can’t be solved using ordinary methods such as , fuzzy set , especially ( mathematical function ) membership . Also the problem that existed in most branches of Math., Geometry , economy and computer science and other sciences this field attracts many researchers to work deeply in studying features and laws of ( soft sets theory ) and developed it by , groups of researches