So what is a Sailing knife? After all, just about any knife can be used to cut a rope.

A true sailign knife was designed for use in maritime situations. It may either be a private venture (commercial) or made under government contract (military). In more recent years, the makers have chosen blade steel and other materials for use in and around salt water. Some common traits of a sailing knife are:

The two most common types of sailing knives are normally classified as Marlin Spike Knives and Rope Knives. Marlin Spikes Knives are sailing knives that have a folding marlin spike. Rope knives are sailing knives that lack the folding marlin spike.

The most common marlin spike (rigger) patterns (click blue text to read entry)
Pattern 317
U.S.N. Approved
NATO Pattern
Sailor's Tool
Pattern 301 or Jack Pattern

Modern Off-Shore
The most common rope knife patterns (click blue text to read entry)
No. 40
Nautical Rescue