What is usually included in the definition of "insurance"?

The definition of "insurance" typically encompasses a policy that provides indemnity for losses. This understanding aligns with the fundamental purpose of insurance, which is to protect policyholders against unforeseen financial risks by compensating them for losses that occur. When a loss happens, the insurance policy is activated, and the insurer will provide the monetary support agreed upon within the contract, thus fulfilling its obligation to the insured.

In contrast, the other options do not correctly align with the concept of insurance. An agreement that lacks legal subject matter does not create a valid, enforceable contract. A contract that only one party can void contradicts the mutual consent and obligations fundamental to insurance agreements, where both parties typically have legal standing. Lastly, a document without any legal consequences would not be a valid insurance policy, as it would not offer any protections or remedies to the insured. Thus, a policy that provides indemnity for losses effectively captures the essence of insurance.