A leader is a heavy length of line that sits between the main line and the rig, keeping the end tackle on the bottom and the line away from the fish. In this group you will find leadcore, lead-free leaders and pre-made leaders. Your choice depends on the rules of the water and on whether you tie your own leaders or prefer them ready made.
Leadcore is a braided line with a lead core running through it. It sinks and follows the contours of the lakebed, so the last few metres before the rig do not lift up in front of the fish. You tie your own leaders from leadcore by splicing loops into each end with a splicing needle.
On many waters the use of lead is restricted. Lead-free leaders are made from heavy materials that contain no lead, and they do the same job of pinning everything down. Always check the rules of your fishing permit before you choose a leader.
Pre-made leaders save time on the bank. They come ready tied, for example for a lead clip or helicopter set-up, so all you need to do is attach the leader to the main line and the rig to the other end.
Always use a leader with a safe system that lets the lead go if the main line breaks. That way a fish never ends up towing the end tackle around behind it, and you can fish with a clear conscience.