Arnis, also known as kali or eskrima/escrima, is the national martial art of the Philippines. These three terms are, sometimes, interchangeable in referring to traditional martial arts of the Philippines, which emphasize weapon-based fighting with sticks, knives, bladed weapons, and various improvised weapons, as well as "open hand" techniques without weapons.

A knife fight is a violent physical confrontation between two or more combatants in which one or more participants are armed with a knife. A knife fight is defined by the presence of a knife as a weapon and the violent intent of the combatants to kill or incapacitate each other; the participants may be completely untrained, self-taught, or trained in one or more formal or informal systems of knife fighting. Knife fights may involve the use of any type of knife, though certain knives, termed fighting knives, are purposely designed for such confrontations – the dagger being just one example.