Generate & Import Coupons

or search frequently asked questions:

Is it possible to generate a coupon just for a specific product or brand?
Can I create coupon codes for a specific customer group only?
Is there a maximum of coupons you can import?
Can I restrict uses per coupon code?
Can I restrict uses per customer?
Is it possible to give discounts via URL?
Message about sending double header in Chrome
Not enough memory or server 500 error while generating coupons in Magento