Plants, like humans, reproduce sexually. While the process may not be as graphic or titillating as it is in humans, plants have sexual organs that perform similar functions. However, in the plant world there are three types of flowers placed within two different classifications. First there is the imperfect plant (unisexual). These are flowers that have either all male parts or all female parts, but not both. Examples of imperfect flowers are cucumbers, pumpkins and melons. The second type of flower is called "perfect" having both male and female parts (bisexual or hermaphrodites). Examples are the lily or the rose. Male imperfect flowers are called "androecious."
The stamen is a stalk like protuberance that grows inside the flower and is the male organ of the flower. The average flower has six stamens situated inside a perinanth (the petals), which are located around the pistil (the female organ found in perfect flowers). Six is not a hard and fast number and often times you'll find more, but seldom less. The collection of stamens are called "androecium".
The filament is the long, thin stalk at the base of the stamen. If you were to think of the stamen as a tree, the filament would be the trunk. The term comes from Latin (filum) meaning thread. The filament is mainly a conduit that carries nutrients as well as supports the anther so the pollen of the plant can be carried off by birds, bugs, wind or rain. In some plants the filament can be exceptionally long, offering the flower an edge in the reproductive process.
Located at the top of the filament, the anther is the pollen producing organ of the plant. The anther manufactures and releases pollen grains thorugh a series of slits or pores. It is this life-creating pollen that sits on the anther until it is carried away by animals, wind or rain (or even people). When airborne pollen lands on the receptive surface (carpel) of another (or the same) flower, pollination has occurred. There is an old wives tale that trimming the stamens on cut flowers will allow them to live longer. This is not true, but the stamens do hold the pollen which can stain clothing so cutting stamens off of a flower display can save a trip to the dry cleaner. This is especially true of lilies.