What is the purpose of "leaders" when fishing?

[Taylor Kash]

What is the purpose of "leaders" when fishing?

[Kkeltic]

You use leaders in finesse type situations, usually in clear water conditions. The lighter leader is less visible to the fish, so your presentation is more natural.

[Big O]

Or a "heavy" leader(copper wire) for fish with TEETH.
To finish Kkeltic's comment.

[buckhunter]

There are many types of leaders. Steel, Mono, Braided, Furled and Weighted Leaders for example. Each have their separate and many uses.

In general a leader is the presentation end of your fishing line.

Most leaders are designed so the fish does not bite through your line. Some leaders make your line invisible to the fish. Some leaders are light and will present a fly lightly on the water. Some leaders are weighted and drop your lure deep into the water.

[steve182]

buckhunter covered it well.

[MLH]

In general, a leader provides a smooth transition from the fly line to the fly. The leader diameter goes from thicker to thinner toward the fly. When the fly line is cast you'll normally see a loop working it's way down the line. When the loop reaches the leader this gradual transition helps "turn" the fly over smoothly for a gentle presentation of the fly. You'll notice problems if the leader is incorrectly sized.

Add a tippet between the leader and the fly to make the leader last longer (leaders can be expensive).

Typical modern leaders are 1.) single line tapered 2.) tied, using different thicknesses of line, and 3.) bimini fashion, using a single diameter of line run through a fixture and wrapped onto itself to create the taper. There are also weighted leaders to get the fly to sink and wire tipped leaders for toothy fish.

Leaders are typically available in mono and flourocarbon. Typically, mono is recommended for floating flies and flourocarbon for nymphing. I have no problem using flouro most of the time. Orvis also make a Hy-Flote, which is hollow tapered. It is very shiny but does floats high.

Choose a leader based on the fly you are using and the presentation needed. For choosing leader/tippet size, generally use a rule of 3. Divide the fly hook size by 3 and select the closest leader. There will be overlap but this will get you close. Longer leaders for more delicate presentation with wary fish in smooth water. Shorter leaders for more broken water and less demanding fish. Wind might also affect choice. With streamers the leader might be only 3-6 feet, sometimes using just straight mono.

One more thing - some finicky but successful fishermen rub their leaders and tippets with clay to cut down the sheen.

[MLH]

Note the difference between flyfishing leaders and normal leaders as described by buckhunter.

[squirrelhunter]

i use leaders fro catfish
cause they tend to roll and they have no teeth but they have like a sandpaper grit on there mouth and if u dont have a leader they will fray the line out
and when ur in a tuornament u cant afford a line break on a big fish

[matouse3]

Another type of leader that use often is a 12-18inch leader from a barrel swivel to a small spinner bait when I trout fish small creeks. This is usually a lighter line and keeps the swivel away from the lure while still keeping my line from twisting.

[870 wingmaster 101]

So toothy fish don't bite your line and so you can put a different bait on quicker(without cuting and retieing).

[survivorman]

when fishing for pike if you dont have a leader the fish will slice right through the line

[bassfisha13]

depends, you can use a leader when fishing for fish with good eye sight, usually a mono leader. sometimes, you can use a metal leader for fish with sharp teeth.

[rudyglove27]

Agreed with buckhunter and + 1 for you sir!!!