The earnings block on a payslip lists each kind of pay on its own line: basic hours, overtime, holiday pay, bonuses (sample guide).
Each line shows the hours or days and the rate, so an employee can check the sum. Overtime is often paid at a higher rate; your contracts and local rules decide which.
If an employee asks about a line, the answer is usually in the timesheet for that period. Keep the timesheets for as long as you keep the payslips.