If a credit or debit card is lost, it can potentially be used by anyone as a credit card unless vendors require photo identification. If someone loses or misplaces a credit card, it's important to report the card as lost or stolen immediately.
By reporting a card as lost, the person limits liability for charges made after the fact. In most cases, the card is deactivated as soon as the person reports the card but not always. After the card is deactivated, the card issuer sends a new card with a different security number, and it retains the same balance as the old card.