Welcome to the foundation of property and casualty (P&C) insurance. Before you can master auto, home, or commercial policies, you need to understand the core vocabulary and principles that every exam question is secretly built on. This guide walks you through risk, the legal principles that make insurance fair, how losses are valued, and the basics of negligence and liability—all in plain language.

Why these basics matter

Almost every question on a P&C exam, no matter how complicated it looks, comes back to a handful of foundational ideas. If you truly understand risk, indemnity, insurable interest, and negligence, you can reason your way through unfamiliar questions instead of memorizing hundreds of facts. Think of this guide as the grammar of insurance.

Risk, peril, and hazard

These three words sound similar and are constantly mixed up on exams. Learn the differences cold.

• Risk — uncertainty about whether a loss will happen. In insurance we usually mean pure risk, which involves only the chance of loss or no loss (your house either burns or it doesn't). Speculative risk involves the chance of loss, no change, or gain (like gambling or investing) and is not insurable.
• Peril — the actual cause of a loss. Fire, windstorm, theft, and hail are all perils.
• Hazard — a condition that increases the chance or severity of a loss. Hazards make perils more likely.

There are three classic types of hazard you must recognize:

• Physical hazard — a tangible condition, like oily rags in a basement or an icy sidewalk.
• Moral hazard — dishonesty or a tendency that leads someone to cause a loss on purpose, such as a struggling business owner committing arson for the insurance money.
• Morale hazard — carelessness or indifference because insurance exists, like leaving your car unlocked since "insurance will cover it." (Tip: morale = lazy attitude.)

How insurers handle risk

People and businesses manage risk in several ways. The exam loves the acronym idea of "avoid, retain, reduce, transfer, share."

• Avoidance — not doing the risky activity at all.
• Retention — keeping the risk yourself, such as a deductible or self-insurance.
• Reduction/control — lowering frequency or severity (sprinklers, alarms).
• Transfer — shifting risk to someone else; insurance is the most common form of risk transfer.
• Sharing — spreading risk among a group.

Insurers rely on the law of large numbers: the more similar units (homes, cars, people) you insure, the more accurately you can predict total losses. This is why insurers want large pools of similar risks.

The legal principles that make insurance work

These principles show up constantly. Master the definitions and a quick example of each.

• Insurable interest — you must stand to suffer a genuine financial loss if the covered item is damaged. In property insurance, insurable interest must exist at the time of loss. You can't insure your neighbor's car because you'd lose nothing if it were wrecked.
• Indemnity — the purpose of insurance is to restore you to the same financial position you were in before the loss, no better and no worse. You should not profit from a loss.
• Utmost good faith — both parties deal honestly and disclose material facts.
• Subrogation — after paying your claim, the insurer can pursue the at-fault third party to recover what it paid. This prevents you from collecting twice and keeps costs down.
• Contribution / other insurance — if two policies cover the same loss, they share the payment proportionally rather than letting you collect the full amount twice.

Definitions to keep straight:

Valuing a loss: ACV vs. Replacement Cost

When property is damaged, how much does the insurer pay? This depends on the valuation method.

• Replacement Cost (RC) — the cost to repair or replace the property with new materials of like kind and quality, with no deduction for depreciation.
• Actual Cash Value (ACV) — Replacement Cost minus depreciation (the wear and tear / aging). ACV pays less for older items.
• Functional replacement cost — replacing with a less costly but functionally equivalent item.
• Agreed value / stated value — a value set in advance, common for art, antiques, and collectibles where depreciation is hard to measure.

Quick example: a 10-year-old roof is destroyed. RC pays for a brand-new roof. ACV pays for a new roof minus ten years of wear. That difference is depreciation.

Coinsurance: the property policyholder's homework

Coinsurance is a clause in property policies that requires the insured to carry insurance equal to a stated percentage (often 80%, 90%, or 100%) of the property's value. If you under-insure, you become a co-insurer and share part of any partial loss as a penalty.

The classic coinsurance formula:

(Amount of insurance carried ÷ Amount of insurance required) × Loss − Deductible = Payment (never more than the policy limit)

Example: a building is worth $100,000 with an 80% coinsurance requirement, so you should carry $80,000. You only carried $60,000 and have a $20,000 loss.

• Required: $80,000. Carried: $60,000.
• $60,000 ÷ $80,000 = 0.75
• 0.75 × $20,000 = $15,000 paid (you absorb the other $5,000).

The lesson: carry enough insurance to satisfy the coinsurance percentage, or you'll be penalized on partial losses.

Named peril vs. open peril coverage

How a policy lists its covered causes of loss is a major exam theme.

• Named peril (also called "specified peril") — the policy only covers perils that are specifically listed. If the peril isn't named, it isn't covered. The burden of proof is on the insured to show the loss came from a listed peril.
• Open peril (also called "all risk" or "special") — the policy covers all causes of loss except those specifically excluded. This is broader coverage, and the burden of proof shifts to the insurer to show an exclusion applies.

Memory hook: open peril = "covered unless excluded"; named peril = "not covered unless listed."

Negligence and liability basics

Casualty (liability) insurance protects you when you're legally responsible for harming someone else. The dominant legal concept is negligence—the failure to act with the care a reasonable person would use.

To win a negligence claim, four elements must all be present:

1. Duty of care — the defendant owed a legal duty to act reasonably.
2. Breach of duty — they failed to meet that duty.
3. Proximate cause — the breach was the direct cause of the harm.
4. Damages — actual injury or loss occurred.

Types of damages:

• Compensatory damages — reimburse the victim, split into special damages (measurable costs like medical bills and lost wages) and general damages (intangibles like pain and suffering).
• Punitive damages — punish especially reckless conduct (often not insurable).

Common defenses to negligence:

• Contributory negligence — in a few jurisdictions, if the injured party contributed at all to their own harm, they recover nothing.
• Comparative negligence — damages are reduced by the injured party's percentage of fault.
• Assumption of risk — the person knowingly accepted a known danger.

Also know absolute (strict) liability, where someone is liable regardless of fault—common with abnormally dangerous activities or certain product cases—and vicarious liability, where one party is responsible for another's actions (an employer for an employee, a parent for a child).

Common exam traps

• Peril vs. hazard: the fire is the peril; the oily rags are the hazard. Don't swap them.
• Moral vs. morale hazard: moral = dishonesty/intent; morale = carelessness/indifference.
• Speculative risk is never insurable—only pure risk is.
• Insurable interest in property must exist at the time of loss, not necessarily when the policy began.
• ACV = Replacement Cost − depreciation. Don't forget to subtract depreciation.
• In coinsurance, the penalty applies even when the loss is far below the policy limit.
• Open peril shifts the burden of proof to the insurer; named peril keeps it on the insured.
• All four negligence elements must exist—missing one defeats the claim.

Quick recap

• Risk is uncertainty of loss; insurers cover pure (not speculative) risk and rely on the law of large numbers.
• A peril is the cause of loss; a hazard increases the chance of loss (physical, moral, morale).
• The principles of indemnity, insurable interest, utmost good faith, and subrogation keep insurance fair and prevent profiting from a loss.
• Replacement Cost pays without depreciation; ACV subtracts depreciation.
• Coinsurance penalizes under-insurance on partial losses; carry the required percentage.
• Named peril covers only listed causes; open peril covers everything except exclusions.
• Liability rests on negligence (duty, breach, proximate cause, damages), with compensatory and punitive damages and defenses like comparative negligence.