If you've ever had your portrait taken in school, you may have noticed some special umbrellas and white boxes on stands. You assumed it had something to do with the lighting, making your picture come out better than if your mom took it. Those boxy looking devices are called softboxes, a crucial element in portrait photography. It is a box that fits over a flash head with a white or silver interior and a translucent front where the light passes through.
Without getting into the mechanisms of lighting, all you need to know is that a softbox will control the light spill. The subject will be illuminated by soft light, evenly, while the background receives minimal light. The softbox will increase the light source, creating softer shadow-highlight transitions. The larger the softbox, the more control you will have and the softer the lighting. Also, the closer you are to the subject, the softer the lighting. They tend to be easier to control and more directional than lighting umbrellas.
Softboxes are especially ideal if you want a portrait with a darker background. You can even achieve a pitch black background without the use of a backdrop. Your subject will definitely appreciate the softbox since it will create a flattering illumination.
Although they may seem like a nuisance to tag along with you, most are collapsible, making them more portable. SuperDigitalCity.com carries a varied selection of softboxes from Creative Light.