Billing is a system of billing customers for the services provided by the company and products sold. The English word bill translates exactly as an "account".
Billing in modern companies is a complex set of programs that allows you to take into account the number of services rendered in various units of measurement, to charge them and issue invoices to customers, taking into account shares and discounts.
Billing in telecommunications and cellular communications works in a "real-time" mode, which means instant writing-off of funds from a subscriber's account for services received by the subscriber (Internet traffic, mobile traffic, SMS and the like). This mode requires the billing system to have high software reliability and stable database operation.
Billing is in the list: Finance