Glossary of Terms

This glossary is an easy reference to some of the terminology commonly used in preparedness circles.

December 30, 2019
ISG Team


When you're trying to learn something new, technical jargon and lingo often make the process frustrating enough to just turn people away.
We want anyone, of any skill and knowledge level, to be able to come to ISG and learn. This glossary is an easy reference to some of the terminology commonly used in preparedness circles. Quite a few of them we think are ridiculous, but we'll share them so if you see us reference them, you'll be able to easily figure out what we're talking about.

We will refresh this as necessary. If you find a term you're unfamiliar with, drop us a line and we'll add it.

We hope you find it useful.


1st Line = A synonym for "everyday carry items", our first line is the equipment we have available to us whenever we're dressed. The 1st line concept is built around the ISG philosophy that our tools augment our resourcefulness; with our first line equipment, we should be able to acquire anything we may need.
For details, refer to EDC below.

2nd Line = 2nd line is a reference to the gear that we add to our 1st line to sustain our efforts long enough to reach a positive conclusion. Typically, we think of 2nd line as our Sustainment Bag, and it should fit seamlessly over our first line gear. However, depending on our mission, it could be a chest rig (fighting), briefcase (if we're constrained by social norms), or messenger bag. The objective is to have enough food, water, and shelter to prevent succumbing to the "rule of 3's" (see below).

3rd Line = 3rd line is a 'catch all' phrase for specialized equipment or provisions we don't carry on us, but can keep as an option. HAM radios, advanced medical gear, food stocks, and vehicle equipment could all be considered third line.

B.O.B. = Bug out Bag. Bugging out is a phrase referring to a reflexive escape from your home under pressure. Our goal is to make sure that doesn't happen by having a carefully thought through plan that accounts for situations that may make your home unlivable. By thinking through those situations before hand (and taking the proper steps), we can use our bags to sustain our efforts, rather than hope they'll keep us afloat like a life vest if our plans sink.

BOK (left) and TOK (right)

BOK/TOK = Bottom of Keyway/Top of Keyway. This is a lock picking method that describes where the tension is applied when attempting to pick a lock. Bottom of Keyway tension is applied for rudimentary locks without security pins.

EDC = Every Day Carry. This is the equipment you carry on you anytime you're dressed. At ISG, we advocate having four items on you anytime you're able: A pocket knife, a flashlight, a multi-tool, and a lighter. EDC can be expanded as necessary to match your level of skill and projected challenges.

GOOD Bag = "Get out of Dodge Bag". Basically the same idea of a Bug out Bag, but a little more sensible.

IINs = Items of Immediate Necessity. These are items that when needed, must be instantly available for use. They should be situated by your dominant side and no additional gear should inhibit your ability to access them. Common IINs are defensive tools (knives and pistols), Tourniquets or hemostatic agents, or rescue tools. Items like our knife or flashlight - while important - usually won't get us killed if we can't access them instantly.

INCH Bag = "I'm never coming home bag". The common concept behind this bag is that you it's what you grab if you had to leave your home never to return. Within our philosophy and in our thinking, this is a poor concept. "I'm never coming home" isn't a bag; it's a mindset and a plan.

Post Disaster Environment (PDE) = This generic term describes any environment we encounter after an emergency has begun: We define emergencies as those events which restrict access to our critical resources (Air, Shelter, Water, Food) for any length of time. As such the phrase "PDE" is not a description of then environment, but a way of identifying that a disaster has recently occurred, or is occurring, there.

RMR = Ruggedized Miniature Reflex. A holographic red dot sight (or dual illuminated amber sight) designed for use on handguns.

Rule of 3's = The Rule of 3's is a principle we use to prioritize our critical resources in emergencies. It states that a human can last 3 minutes without oxygenated blood, 3 hours without shelter in bad conditions, 3 days without water, and 3 weeks without food. Our goal is always to address the threat within the first third of the timeframe. For example, while you can survive for 3 minutes without oxygen, most people will be panicking by the time the first minute is up. The same goes for shelter, water and food.

SoV = Spheres of Violence. Spheres of violence is an ISG concept that distinguishes how violence affects people in different groups. We believe that the violence experienced by a military infantryman is different than that experienced by Special Operations, police, contractors, or civilians. Spheres of Violence categorizes violence by whether or not it is Social (between two willing parties) or Asocial (an aggressor/defender relationship) and by whether it is Institutional (violence done on behalf of an organization) or Interpersonal (Violence done between individuals or very small groups).

Sustainment Bag = The Sustainment bag is the ISG answer to the "bug out" bag. Rather than being a niche bag that we only grab in emergencies, the Sustainment bag is something we can use on a daily basis for ease, adventure and recreation, or for sudden emergencies. The goal with the sustainment bag is to have the necessary equipment and sustenance to see us through while we address the Rule of 3's (above). In our view, this bag should be taken when you hike or camp and trained with when you build skills or fitness, rather than tucked away in a corner or a vehicle in case an emergency happens.

TEOTWAWKI = prepper fantasy speak for "The end of the world as we know it", which is an opportunity to get in touch with your inner fuedal warlord in popular culture. In reality, it's a situation that causes a major bottleneck in the human population, such as the Toba Eruption, or a meteor strike.

Type 1 = Type 1 is in reference to the 'Type 1 emergency' from Understanding Emergencies. It refers to short duration, high intensity emergencies that immediately threaten your life or the lives of those near you. By their nature, these direct threats don't last long because they either succeed, are solved by those affected, or they are escaped. Examples of Type 1 emergencies include: car crashes or fires, violent assault, attempted murder, sudden natural disasters (earthquakes/tornados), exposure to elements, or threat of drowning. The Type 1 emergency is solved using your EDC and its accompanying skills.

Type 2 = Type 2 is in reference to the 'Type 2 emergency' from Understanding Emergencies. It refers to moderate intensity, moderate duration emergencies that generally impact the availability of critical resources. These scenarios generally affect broad areas and one of their critical elements is the increased likelihood of embedded Type 1 Emergencies (that directly threaten you). An example of a Type 2 emergency would be a blizzard that knocks out power and limits shipment of goods. While the scenario itself is unlikely to kill you, if you found yourself stranded in your vehicle during the blizzard, exposure to elements (at Type 1) could. The Type 2 is managed using your backpack (sustainment bag) and it's accompanying skills.

Type 3 = Type 3 is in reference to the 'Type 3' emergency' from Understanding Emergencies. It refers to a low intensity, indefinite emergency that fundamentally changes the way you live. And example of a Type 3 emergency would be a regime change, a socio-economic collapse, a civil war like that in Croatia, or massive man-made or natural disasters, such as nuclear war or meteor strike. The Type 3 emergency features increased disruptions to supply chains and critical resources (such as infrastructure) and the embedded Type 1 emergencies that attend resource scarcity.

UE = Understanding Emergencies. Understanding Emergencies is ISG's flagship concept, and it serves as the foundation and capstone of our content here. It is referenced often and the UE template aligns types of emergencies with the lines of equipment necessary to manage them.

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