Most insurers define accidental damage as an unintentional one-off incident that harms your property or its contents.
Most standard policies cover key items like home entertainment, but there may be varying exclusions depending on your insurer.
Your need depends on your circumstances - many accidental damage claims come from people with young children.
It's also important to know what's covered under your standard policy. Checking the small print is the best way to make sure you've got adequate cover.