Many creeping and/or weak-trunked plants require supports to stop them falling over. In nature, creeping plants will grow up tree trunks and cliffs.
Gardeners often use supports to make more efficient use of vertical growing space -- growing cucumbers or tomatoes on a support instead of allowing the vines to sprawl around the ground uses fewer square feet of garden space per plant.
Supports may be houses, trellises, netting, canes, posts, etc.
Use this tag for all questions about providing support to plants.