The square knot or even the joining knot is a simple but effective method for securing two equally sized ropes and is among the most commonly known and used knots. Originally used by sailors to reef sails because in heavy seas the knot can be released with one hand. However it is not considered to be safe for long term use and should never be used to connect unequally sized ropes as the knot will eventually slip.

# How to tie a reef knot.

Take one end of the rope in each and hand and pass the right over and then under the left, now with the same rope now in the left hand, pass left over right and under. You should now have a knot which is symmetrical and resembles a figure eight. As a scout you may have learned the mantra "right over left and under, left over right and under".

# How to untie a reef knot

Grasping either one or both of the top loops of the knot you can easily 'break' any tension that has caused the knot to close, if too much pressure has been applied and the knot will not 'break' easily the application of a marlinspike will create enough space to loosen the knot.

# Footnote

ASCII art, don't do it folks, embrace the power of the word.

The reef knot is also known as a square knot; in fact, the latter name is much more common (at least in my experience, growing up in the USA and being an Eagle Scout in the Boy Scouts of America).

Other useful knots for joining two ropes are the sheet bend and the Carrick bend.

A rough ASCII art picture of one might look like this:

```         @@@@     :::::    @@@@@  ::::
@@@@@@ :::::::::@@@@@@@::::::
@@:::::   :@@@@@  :::::@
::::@@@@@@@@@:::::::@@@
::::  @@@@@   :::::  @@@@
::::                 @@@@
::::  @@@@@   :::::  @@@@
::::@@@@@@@@@:::::::@@@
@@:::::   :@@@@@  :::::@
@@@@@@@@@@@@@@@ :::::::::@@@@@@@::::::::::::::::::
@@@@@@@@@@@@@     :::::    @@@@@  ::::::::::::::::
```

Notice that the ropes come out the same side they came in; if you miss, you've created a granny knot. Another problem can occur, even if you've routed the ropes correctly: if you tighten only one rope, you can end up with that rope going straight through, and the other rope forming a lark's head hitch around it. Usually, this is not what you want.

The reef knot/square knot is also known in some circles as the joining knot, and is the preferred knot in several various cultures' wedding ceremonies, which is where we get the phrase tying the knot for marriage.