1:::::---set off and carry forward comes under taxation. i 
vl take an eg.to explane set off-- mr.a has got 2 business 
one is cloth shop and another is coffee shop...at the end 
of d year...owner faced a loss of 50000 from cloth shop and 
profit of 60000 from coffee shop.(60000-50000) therefore 
the owner is only liable to pay tax on 10000 rs because 
according to income tax act. his loss should be recovered 
from his profit.
note:- both the business should come under one head..
2:::::---carry forward ---taking same senario if mr.a faced 
a loss of 100000 and profit 0f 30000 ...den his profit 
amount will be adjusted to his loss amount and he will not 
be liable to pay any tax...whereas (100000-30000) leftover 
amount vl be again adjusted to next year profit....if he 
coundnt recover his loss amount next year...d maximum time 
he can take is 8 years..