Fishing bobber from WoW

Fishing lures are items that allow you to increase your fishing skill for a short amount of time.

There are various types of fishing lures and they may be bought from vendors or crafted by an engineer.

Lure +Skill Min skill Length Source
 [Glass Fishing Bobber] +2 0 10 EK/Kalimdor fishing dailies
 [Shiny Bauble] +3 0 10 Vendors (50c)
 [Aquadynamic Fish Lens] +9 50 10  [Stendel's Bane] (Westfall)
 [Nightcrawlers] +5 50 10 Vendors (1s)
 [Flesh Eating Worm] +7 100 10 Rotted One (Duskwood)
 [Bright Baubles] +7 100 10 Vendors (2s 50c)
 [Aquadynamic Fish Attractor] +9 100 10 Vendors (2s 50c)
 [Sharpened Fish Hook] +9 100 10 Outland dailies
 [Glow Worm] +9 100 60 Northrend dailies
 [Feathered Lure] +9 100 10 450 Cooking
 [Heat-Treated Spinning Lure] +10 1 (Cataclysm Fishing) 15 Engineering
 [Worm Supreme] +10 100 (Draenor Fishing) 10 Draenor fishing
 [Day-Old Darkmoon Doughnut] +10 1 10 Darkmoon Faire (temporary duration)

Fishing lures create a temporary buff to fishing skill as an enchantment on your fishing pole.

Fishing lures provide much greater enhancement to fishing skill than is available through other fishing gear.

Most fishing lures are used by right-clicking on the lure while you have a fishing pole equipped. This consumes the lure and creates a temporary fishing skill buff on the fishing pole. The Weather-Beaten Fishing Hat is not a lure, but right-clicking on the hat to use it allows you to "pull a lure from the hat" and apply it - with a ten-minute cool down, you can apply these continually and keep a +75 buff on your fishing rod. Only one fishing lure can be used at a time.

Most fishing lures have a fishing skill requirement. The Weather-Beaten Fishing Hat has no explicit requirements, but it is Bind on Pickup, you must be level 10 to do the daily fishing quests that award it.

Fishing lures can increase your fishing skill to be able to fish in a more difficult location or to be able to fish there reliably. Fishing reliably means less fish 'get away' - making your gaming time more productive. Fishing skill above the skill required for 100% catch rate is wasted, so you do not always need to equip a lure. For example, the +25 fishing skill  [Shiny Bauble] lure would be helpful when you are first starting out (or you can endure a few missed fish), but once you've caught around 30 fish, it would be superfluous to use a lure in your starting area.

Even with maximized skill and many other skill enhancements, it is possible to fish up junk in the highest-level areas, such as Uldum. Thus, fishing lures are always useful.