I am presenting here the Albright Knot. Albright Knot is considered as a fishing knot.
The Albright Knot is a versatile knot that has a wide range of uses. It is only moderately easy to tie but it is suitable for joining different types of fishing line, e.g., Monofilament to Braided, or Braided to Wire. The Albright Knot is one of the most reliable knots for joining lines of greatly unequal diameters or different materials such as monofilament to braided line. Many experienced fly fishermen prefer the Albright to attach their fly line to leader material, some even going so far as to cut off a factory welded loop to use the Albright! It certainly is the go-to choice knot for tying Dacron backing to fly line for most fly fishermen. It is easy to tie and should be in every angler’s knot arsenal. 

It is also useful when joining monofilament fishing lines with different diameters. It is commonly used to join the fly line to the backing line but can be used whenever you wish to join two fishing lines together.

The Albright is well suited to slide readily through the guides when a fish pulls out enough line to reach your backing. Some anglers coat the knot with a rubber-based cement to make it even smoother and more secure.

Instead of presenting here some kind of animation knot, pictures or videos inconvenient for reproducing the knot (as some websites do) we provide demonstration of tying knots using YouTube videos directly by hands. Videos are taking with such angle that viewer is experiencing a full presence in tying process and can actually repeat the creation of the knot by his/her own hands. In many cases we are forming the Knot using colored ropes for better understanding and memorizing of the way how fancy rope work was done. In videos (such as "Fishing Knots Under 30 seconds) we are also demonstrating tying knots in slow motion inviting viewer tying knot together with us.

Also you can go directly from here to playlists related to fishing knots: