Time zones simply create a workable 'day' and 'night'. Ifcountries didn't use time zones (and the whole planet worked on thesame time), people would be going to bed at (for example) 9am justbecause it was dark then. Time zones bring sensibility to dailylife.The only disadvantage - is having to adjust to different timeswhen you travel overseas. For example - it might be 8am when youdepart, but (after travelling through a number of time zones) - itmight only be 2am local time.