Deduction is a basic approach used in Logic to arrive at valid conclusions. In deduction one arrives at particular statements from general statements, and premises are the informative statements on the basis of which conclusions (or deductions) are made. In the correct kind of deductive reasoning, the conclusions follow necessarily from the premises that is given.
Premise 1 - All companies other than charities are only interested to make more money from their customers
Premise 2 - Transportation companies in the country are not charities
Deduction - Transportation companies in the country are only interested to make more money from their customers
Premise 1 - All teachers shall not talk about espousal of homosexual values
Premise 2 - Gay teachers talk about espousal homosexual values
Deduction - Gay teachers are not teachers
Premise 1 - Police shall be deployed for all riots
Premise 2 - Action figures and toys are seen in riot
Deduction - Police shall be deployed to stop action figures and toys in riot
Note: The above deduction follows necessarily from the two premises given. It should be noted, however, that the process of deduction does not say anything about the truth of the premises themselves. The premises must be true before they are used for any deduction because if the premises are invalid, the deductions that necessarily follow will also be invalid.