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Bowline Knot Details

Uses: The Bowline (ABOK # 1010, p 186) makes a reasonably secure loop in the end of a piece of rope. It has many uses, e.g., to fasten a mooring line to a ring or a post. Under load, it does not slip or bind. With no load it can be untied easily. Two bowlines can be linked together to join two ropes. Its principal shortcoming is that it cannot be tied, or untied, when there is a load on the standing end. It should therefore be avoided when, for example, a mooring line may have to be released under load.

Step By Step Bowline instructions
Also see Bowline on a Bight
Also see Running Bowline

Clove Hitch using Half Hitches Details 

Uses: As shown in this animation, the Clove Hitch can make a quick hitch. Only two Half Hitches were used. To make the hitch secure, additional Half Hitches must be added in the same manner. The Clove Hitch has various applications. For example, in the theater it is used to adjust the height of stage curtains hanging from a bar; and in boating it can be used to initially position a fender hanging from a rail. Both are described in the section about the Clove Hitch tied by Threading the End.

Dangers: As stated above, the Clove Hitch's problems are slipping and binding:

Slipping: I watched a friend trying to dock his 53' Hatteras. Each time the bow mooring line was; handed to the marina assistant, he used a clove hitch to attach the line to the dock's post. The; offshore wind was blowing the stern away so my friend used his engines to swing the stern in.       Each time he did so the strain was too much for the Clove Hitch, which slipped undone. This process was repeated seven times despite increasingly forceful requests that some other knot       be employed to secure the line. Reviewing the events later it became apparent that the assistant    was using the only knot he knew. It is not a knot to be used alone.Finally, if you make the knot secure by stacking on additional Half Hitches, i.e., multiple clove hitches, then you are inviting a major strain to cause the earlier turns to bind tightly and become impossible to untie. So, if on a boat you feel an urge to use a clove hitch - resist! Choose something else unless you are merely hanging a fender.
Binding: Finally, if you make the knot secure by stacking on additional Half Hitches, i.e., multiple clove hitches, then you are inviting a major strain to cause the earlier turns to bind tightly and become impossible to untie. So, if on a boat you feel an urge to use a clove hitch - resist! Choose something else unless you are merely hanging a fender.

Step By Step Clove Hitch instructions

Round Turn and Two Half Hitches

Uses:A Round Turn and Two (or more) Half Hitches is useful for attaching a mooring line to a dock post or ring although probably less secure than the Anchor (Fisherman's) Hitch.

Step By Step Round Turn and Two Half Hitches instructions

Sheet Bend Details

Uses: The Sheet Bend (ABOK # 1431, p 262) is recommended for joining two ropes of unequal size. The thicker rope must be used for the simple bight as shown. It works equally well if the ropes are of the same size.

Step By Step Sheet Bend instructions

Square Knot (Reef Knot)

First Knot: The Square (Reef) Knot is usually learned when we tie the laces on our first pair of shoes. Admittedly it is usually a bow that we tie - but the underlying knot is a Square (Reef) Knot. We also learn just how unsatisfactory the knot is. It slips, it comes undone, it jams, and it is all too easy to tie a Granny instead which behaves even less well.
Purpose: It is intended to be a binding knot and, tied in the right material against a curved surface, the first Half Knot may bind – but it cannot be trusted. That is why surgeons use an extra turn in the first Half Knot – to achieve the binding required while they prepare the second Half Knot.
Caution: "There have probably been more lives lost as a result of using a Square Knot as a bend (to tie two ropes together) than from the failure of any other half dozen knots combined." Never use it for critical loads.
Uses: Provides a quick and convenient stopper knot to prevent a line sliding out of sight, e.g., up inside the mast. Its virtue is that, even after it has been jammed tightly against a block, it doesn't bind; it can be undone easily. This virtue is also, occasionally, a vice. The figure 8 can fall undone and then has to be retied.

Step By Step Square Knot (Reef Knot) instructions

Also Good to Know:

Cleat Hitch

Uses: The Cleat Hitch secures a rope to a cleat. It is deceptively simple and an unwary skipper who invites visitors to cleat a mooring line may be astonished and dismayed by the unsatisfactory results.

Step By Step Cleat Hitch instructions

Figure Eight

Uses: Provides a quick and convenient stopper knot to prevent a line sliding out of sight, e.g., up inside the mast. Its virtue is that, even after it has been jammed tightly against a block, it doesn't bind; it can be undone easily. This virtue is also, occasionally, a vice. The figure 8 can fall undone and then has to be retied.
Comparison: The Figure 8 should be compared to other common stopper knots. It is much better than the simple Overhand Knot which is smaller and can bind so tightly that it can be really difficult to undo. However, both the Double Overhand Knot, and the Ashley Stopper Knot, make better Stopper knots because they are larger and more stable.
Climbing: For climbing, where safety is paramount, the Double Overhand is the preferred Stopper knot. However, the Figure 8 is important to climbers because it is the basis for tying the Figure 8 Bend (Rope Join), the Figure 8 Loop Follow Through, and the Double Figure 8 Loop.

Step By Step Figure Eight instructions