Why is a ship called a liner?

Ships that operate daily do so based on a fixed route or a ‘line’. These regularly scheduled voyages are known as lined voyages. The sea vessels operating on these lined routes following a fixed timetable and carrying cargo are known as liners. These ships are constructed according to set standards to improve shipping quality. Liners can be cargo or cruise ships that function between fixed ports. Since liners work routinely, they help avoid shipment delays unless there is a natural calamity or emergency. It becomes feasible for traders who frequently ship goods internationally as they work time-bound shifts.