DISCOUNT RULES
Using discount rules feature you can apply discounts on set of products and you can define the rules that on which particular products the standard discount have to be applied.
For examples, you can have a discount rule that says 'Apply 5% discount on all Fiction category books written by Chethan Bhagat'
Another example can be 'Apply 10% discount on all Mens and Childrens categories'


If you want to apply discount for set of particular products, You can create a tag for these products with particular name and you can set discount on all the product with that tag name.