Pollination help plants transfer their pollen grain from the anther to the stigma of the same or of different flowers. Agents such as insects, wind, water etc can help in this process. This helps the male gamete(in the pollen grains) to reach the female gamete (male gamete from pollen reaches the ovary through the style) and help in reproduction by fusion of gametes. This helps plants produce seeds an fruit and thereby new offsprings. Pollination, in turn, benefit the insects because they can collect nectar from the flowers during the process.