Below, is the accompanying text.
A sailor judges knots for their holding qualities and also their ability to be quickly unfastened, without regard to the strain they have been subjected to. A knot’s main office is to hold, without working loose or slipping, yet they do occasionally fail absolutely to accomplish this, when made by inexperienced hands. The accompanying diagrams show some of the simpler knots that may be of everyday use. In these, the mode of formation can be readily discerned, because the rope’s position is shown before tightening.
The overhand knot, Figure I, is probably the simplest of all. It is used only for making a knot at the end of a rope to keep it from fraying or to prevent another know from slipping. If a slight change in formation is made, as in Figure 5, it develops into a slip knot or, as it is sometimes called, a single sling, and its purposes are obvious.
A double sling is represented in Figure 6, and though it is slightly more complicated, it is considerably more useful for any purpose where a rope is to be attached to a bar or beam and stand a steady strain. Probably for convenience and emergencies no knots equal the bow-line, Figure 7, because it will not slip or give, no matter how great the tension; in fact, the rope itself is no stronger, and the instant the strain ceases it can be untied as easily as a bow.
When the end of a rope is to be secured, the two half-hitches or clove hitch, Figures 2 and 3, are of great importance, for either of these bends can be attached instantly to almost anything, and their holding powers are exceeded by none.
The square knot, Figure 4, can be used for infinite purposes, from reefing a sail to tying a bundle, the advantage being, if made properly, of resisting any separating strain on either cord, and yet can be untied immediately by pulling one of the short ends.
One of the best and safest slip knots is shown in Figure 9, made with the overhand at the end, which, until loosened by the hand, maintains its grip. When a rope requires shortening temporarily the sheep shank, Figure 8, affords a means of so doing. This knot can be applied to any part of the rope without reducing its strength of rectilineal tension.An additional useful farming knot is the Trucker's Knot.
Source: The six Boy Scout knots.