BPO categories are front-office customer services (such as tech support) and back-office business functions (such as billing).
Business process outsourcing is a form of business where a company sets contract with an outside third party company for the completion of a non primary business task through electronic process in exchange of a certain amount of payment for the third party.
Business process outsourcing usually have 2 categories:
1. Back office functions: Payroll often regarded as billing services
2. Front office customer services : Customer call centers often regarded as tech support