Spanking is when a hand or a paddle is slapped against the bottom. Painful or not very painful depending on your intentions, spanking can be used to add extra sensations. Spanking can be integrated with role play, as a punishment in a dominant/submissive game or during intercourse for more excitement.
A flogger is a whip with many tails which can be used anywhere on the body but particularly the back, bottom or thighs. It produces a pain on more intense level. Beginners should start with a flogger made of soft materials like fur and suede, with thick tails and rounded ends.
The slender tip on whips offers a much more intense sensation than a spanking paddle. For beginners, the easiest and safest way to experiment is with a riding crop. A bull whip is more difficult to use and will produce a cracking sound and a sensation that is similar to being cut.