Self-defense (self-defence in many varieties of English) is a countermeasure that involves defending the health and well-being of oneself from harm.The use of the right of self-defense as a legal justification for the use of force in times of danger is available in many jurisdictions, but the interpretation varies widely.
Many styles of martial arts are practiced for self-defense or include self-defense techniques. Some styles train primarily for self-defense, while other martial or combat sports can be effectively applied for self-defense. Some martial arts train how to escape from a knife or gun situation, or how to break away from a punch, while others train how to attack. To provide more practical self-defense, many modern day martial arts schools now use a combination of martial arts styles and techniques, and will often customize self-defense training to suit the participants' lifestyles, occupations, age groups and gender, and physical and mental capabilities.
A wide variety of weapons can be used for self-defense. The most suitable depends on the threat presented, the victim or victims, and the experience of the defender. Legal restrictions also greatly influence self-defence options.
In many cases there are also legal restrictions. While in some jurisdictions firearms may be carried openly or concealed expressly for this purpose, there are also jurisdictions with tight restrictions on who can own firearms, and what types they can own. Knives, especially those categorized as switchblades may also be controlled, as may batons, pepper spray and personal stun guns and Tasers - although some may be legal to carry with a licence or for certain professions.
Non-injurious water-based self-defense indelible dye-marker sprays, or ID-marker or DNA-marker sprays linking a suspect to a crime scene, would in most places be legal to own and carry.
Everyday objects, such as flashlights, baseball bats, newspapers, keyrings with keys, kitchen utensils and other tools, and hair spray aerosol cans in combination with a lighter, can also be used as improvised weapons for self-defense. Tie-wraps double as an effective restraint. Weapons such as the Kubotan (pocket stick) have been built for ease of carry and to resemble everyday objects.Ballpoint pen knives, swordsticks, cane guns and modified umbrellas are similar categories of concealed self-defense weapons that serve a dual purpose.