When it comes to the plant kingdom, flowering plants are the most developed plants and flower is the base for their sexual reproduction. When they get pollinated, the fruits and seeds result. Finally, they also get spread through animals and wind in order to spread the plants. In order to attract animals and birds to facilitate pollination most flowers have become attractive and there are others that have fragrances.
Though the scientific need of a flower for a plant is its reproduction, most often they are used by people for decorative purposes. Use of flowers for such purposes has been practiced from ancient times. They are used for decorating homes day to day and also on events such as weddings. Often, they are used for religious purposes also. Rituals, medicine and food are the other purposes served by flowers.
If you look at a flower carefully you will find several parts. Normally it will be located at the end of a short stem. The outermost part is the calyx. It is the one encloses the bud. Normally, it has five lobes and is of green color. Next is the corolla that has the petals. Then you have the stamens that consist of stalks and filaments. Finally, the innermost part of the flower is there. It is called the Gynoecium and it has the carpel on which pollen has to fall for the flower to be pollinated. At its bottom you get the ovaries.
Unlike animals, plants are not able to move in search of mates. Instead, they attract insects and animals to get their flowers pollinated. Most flowers produce honey in order to attract insects. When insects go in search of honey in a flower the pollen will fall on them and when they go to another flower they pollinate it without their knowledge. There are also some flowers that have developed mechanisms to get their pollination done through air.
There is the possibility of cross pollinating flowers in order to produce bigger and more attractive ones. Also it is used for the creation of hybrid plants. Very often this method is used for the development of high yielding varieties of rice paddies. In addition to that any kind of plants that cannot be budded has to be developed only through cross pollination under controlled conditions. For this type of cross pollination a high quality flower has to be chosen. Pollen also needs to be collected carefully for the purpose.