The expression pay-as-you-throw, also often appearing in non-hyphenated form and sometimes abbreviated to PAYT, has been used in the United States since the 1970s, but has not gained currency in British English until quite recently. Its more widespread recognition seems partly attributable to its catchy similarity to the expression pay-as-you-go, now in regular use to refer to a system for paying for mobile phone calls. This system is also known as pay-as-you-talk and is often abbreviated to PAYT too.