First of all, we should understand that cephalosporins are divided into four generations: the first generation cephalosporins such as cefthiophene, cefotiadine, cefazolin, cefalexin, cefradine, cefadroxil and so on. The latter three can be taken orally. The second generation cephalosporins, such as cefuroxime, cefuroxime, cefoxitin, cefmethoxythiophene and cefaclor, are the third generation cephalosporins, such as cefotaxime, cefoperazone, ceftriaxone (triazine), cefotaxime (tazidime) and cefixime (Dalifen), and the fourth generation cephalosporins, such as cefazolin. The pioneers we often say belong to the first generation cephalosporins: cefotaxime (cefotaxime 1), cefotaxime (pioneer 2), cefantitoxin (pioneer 4), cefazolin (pioneer 5) and cefradine (pioneer 6).