Billing models refer to the various methods businesses use to charge customers for their products or services. Common models include subscription-based, where customers pay a recurring fee for ongoing access, and pay-per-use, where charges are based on actual usage. These models help companies predict revenue and manage cash flow. Another popular billing model is tiered pricing, which offers different levels of service at varying price points. This allows customers to choose a plan that best fits their needs and budget. Understanding these models can help consumers make informed decisions about their purchases and services.