A certificate of insurance is the document that confirms the main details of a person’s cover. It usually identifies the insured person, the period of insurance, and the reference or policy number connected to that cover.
It is an important document, but it is not the same thing as the full policy wording. The certificate confirms the specific cover details for the insured person, while the wording explains the rules, exclusions, conditions, and how claims are handled.
If someone asks you for proof of cover, this is often the first document they mean. If someone asks you for the full terms, they may also need the policy wording or a product information document.