The development of plants under the influence of light. All the processes crucial to the growth and development of plants are triggered by light, including seed germination, stem elongation, chloroplast formation, and flowering. These light responses are mediated by various photoreceptor systems, including phytochrome, which responds to red and far-red light, and cryptochrome, which is sensitive to blue and green light. These photoreceptor molecules interact with cell signalling networks to regulate the expression of genes involved in development and also influence the production of plant hormones, notably gibberellins and brassinosteroids.