Sleep before exam?

Your brain isn't a machine and it needs adequate rest. Depending on one's body and mind it is suggested anywhere between six to eight hours of sound sleep is essential. As mentioned above by the learned members, you must give reasonable time for sleep, so that you can have a productive and effective studies. 

Mr T.N.Manoharan says that if you want to study sacrificing sleep a little bit goahead with studies but if your body wants to take rest then sleep