Payroll involves calculating employee pay and ensuring tax compliance. It includes developing pay policies, defining pay components, gathering inputs, calculating deductions, releasing pay, and depositing taxes. The process has three stages - pre-payroll planning, actual payroll calculation, and post-payroll activities. Managing payroll is challenging due to statutory compliance requirements and dependence on inputs from multiple sources. Businesses can manage payroll through Excel, outsourcing, or payroll software, which automates calculations and integrates inputs.