[Joni]

Curtis hit the nail on the head again. Specially on floating line and the better the line the easier it is to cast and it will last longer. The pricie ones have a slick coating on them and they don't require cleaning or dressing (which I still clean mine once a month) But, there is Cortland Sylk and I am sure others that are fantastic lines, but they do require the mantinance.
The Double Taper (DT)
A double taper fly line is a fly line that is heavy and thicker middle section, and then gradually loses both width and weight the closer it gets to the end of the fly line. What is important to remember about double taper fly line is that it is balanced - both ends of the fly line weigh the same and each end gradually increases in width and weight the closer it gets to the middle section of the fly line at an equal rate.

For example, at double taper fly line is 90 feet long. In the first 15 feet of the fly line (the end closest to the fly), the fly line increases both in width and weight as it travels towards the middle of the line. Upon reaching 15, the fly line reaches the middle section of the fly line - which is the maximum width and weight of the fly line. This middle section of the fly line continues for 60 feet, with the same weight and width. Then, in the final 15 feet of fly line (the end closest to the reel), the fly line begins to lose both width and weight at the same rate it was gained on the other end of the fly line.

Double taper fly lines use to be the most popular fly line, especially for trout fishing. The light taper on the front of the fly line allows for the fly line to land on the water without creating a spectacle, and the weighted middle of the fly line allows for solid general fly casting. The double taper line is also excellent for casting using either S casts or the roll cast, as the weight in the middle of the fly line makes this easier. The double taper fly line also allows it to be "reversed". Should the front of the fly line begin to wear out, all you need to do is to turn the fly line around.

However, the double taper fly line, while still popular, has lost ground to the weight-forward taper. This taper is described next.


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The Weight Forward Taper (WF)
The weight forward taper fly line is the most popular fly line on the market today - as well as being the most expensive.

A fly line that has a weight forward taper has extra weight and width built into the first 30 feet of the fly line, although some specialized lines extend or shorten this taper. The rest of the fly line will then be level, of equal weight and width for the remainder of the fly lines length. The advantages of a weight forward fly line include longer casts, the casting of larger flies and more effective casts in windy conditions.

One thing to remember - because extra weight and width are on one end of the fly line, it is crucial that the line be put on correctly. You want the extra weight and width of the fly line to be on the end of the fly line, not tied onto the reel! A weight forward taper fly line also cannot be reversed in the event the end of the line becomes cracked or damaged.

For beginner anglers, weight forward fly lines are the recommended fly line to get. They are easier to cast than other fly lines, allowing for better control and longer casts. Additionally, weight forward fly lines are always used when casting things like bass bugs and streamers - in short, heavy things.

This has it's flaws also due to the fact that a lot of manufacturers are now coming out with special WF for different species, but the general idea.
There is also level lines and Triangle tapers, but WF and DT are the most used.