Every pet insurance policy has two parts: the standard policy wording that applies to everyone on that policy type, and the schedule, which is the bit specific to you. The schedule is where your pet's name, breed and age appear, along with the particular cover level you've chosen, your excess amount, the start and end date of the policy and any specific exclusions or endorsements that apply to your policy rather than all policies.
Think of the policy booklet as the rulebook that applies to all customers, and the schedule as the page at the front that says here's how those rules apply to your specific policy.
The schedule is worth reading carefully when you first take out a policy and again at each renewal, because this is where any individual exclusions will appear. If you declared a pre-existing condition when you applied, the schedule may note that condition as excluded. If your pet's details have changed, the schedule should reflect that. If there are any endorsements that modify the standard terms for your specific policy, they'll be listed here.
"The schedule is where any individual exclusions on your specific policy will appear. This is the bit most worth reading carefully."
It's a short document, usually just a page or two, but it's one of the most important ones in the pack because it tells you exactly what applies to your cover rather than the general terms.