There are four generations of quinolones:
First generation: nalidixic acid, nitrofurantoin. Usually used in urinary tract infection. This group was called old quinolones.
Second generation: ciprofloxacin, levofloxacin, ofloxacin, norfloxacin, and lomefloxacin. From this generation on, the next groups are called new quinolones/fluoroquinolones; due to their systemic effect.
Third generation: gatifloxacin, gemifloxacin, grepafloxacin, sparfloxacin
Fourth generation: moxifloxacin, trovafloxacin