A fishing rods action
The action of a rod describes how it will bend when pressure is applied to the tip. A rod with a fast action will bend only in the top 1/3 while a rod with slow action will bend to the bottom 1/3 of the rod.
Power or backbone of a fishing rod
A fishing rod's power or backbone is related to its line strength. It is important to properly match the rod with the line strength. Rods with more backbone will use stronger/heavier fishing line. A rod with a lot of power can break a line that is too light and a line that is too heavy can snap a rod that does not have enough backbone. Rods that have a lot of power are used when leverage and lifting power is needed. These rods also tend to be heavier and can be more difficult to cast.
Fishing with spinner baits requires a lot of casting. You will want a rod that is lightweight and sensitive. The fish will often bump the bait before engulfing it and you need to know this to be ready to set the hook. A rod that is 6 feet long will give you more casting accuracy, but a 7-foot rod will give more distance. It will also give more leverage for quickly setting the hook and controlling the fish once it is on. Look for a bass fishing rod that is between these two measurements for best casting accuracy. Bass fishing rods used for spinner baits are also good for buzzbaits and other lures that are moved quickly through the water.
Worm and jig fishing
Finesse fishing is slow and deliberate. Bass fishing rods for worms and jigs need to have a medium action for leverage and a fast tip. Most of the time a bass will either pick up the worm or jig off the bottom or more likely engulf it as it is falling, so you need to be able to feel this. You will want a rod that is 6 1/2 to 7 1/2 feet long with medium action and medium fast tip.
Being able to catch bass in heavy cover requires a rod with a lot of power and leverage. With flipping or pitching you are not actually casting the bait. Instead, you will be holding the rod level to the water and swinging the bait out like a pendulum. You will see the strike, so sensitivity of the rod is not as important as power. The tip should be fast to aide in flipping or pitching the bait. The rod should be 7 1/2 feet long. Longer rods provide better leverage, but are harder to flip or pitch the bait. It should have medium action and a lot of power. It is not uncommon for bass anglers to use 20 lb test line when flipping.
Crankbaits and top water lures like spinner baits require a lot of casting. You want this rod to be lightweight and sensitive. Strikes from fish hitting topwater lures will be seen so sensitivity is not that important. However, strikes from crankbaits diving below the surface will have to be felt. Crashing crankbaits into underwater objects is a technique that increases the effectiveness. A sensitive rod tip will let you feel when a crankbait hits a submerged object. Longer rods of 7 to 7 1/2 feet give more distance to casts and make casting larger baits easier. Shorter rods of 6 to 6 1/2 feet have more accuracy. The choice of rod length will be determined more by bait size when using crankbaits and top water lures. The fishing rod used for crankbaits and topwater lures will generally be 6 to 7 feet long and lightweight. It will have a medium action and a fast tip for crankbaits.