Pinterest is a site that is a lot like an online scrapbook. It allows users to collect pictures and comment on them. The pinterest user can either post their own pictures or collect and re-post pictures from others on the Internet. These pictures can be organized into collections called boards. The majority of Pinterest users are female. Many of these pinterest boards are centered around such things as home decoration, wedding planning, children, etc. If you have a business that lends itself to photos, you may do well on Pinterest. Such businesses would include bakeries, wedding planners, decorators, artists, photographers, arts and crafts, etc. Pinterest offers special accounts for business, see business.pinterest.com. For the business account, you'll need to create a profile to tell everyone about your business, and probably start with about three boards for various aspects of your business. To make it easier to pin photos to a board, Pinterest makes extensions or plug-ins for all major browsers that will put a 'pin-it' button up in the toolbar of your browser.
To make Pinterest start working for you, start interacting with other users on the site to help get the word out about your offerings. Pinterest will provide analytic reports for you to show which of your images are being pinned by others, so you can learn what other users like. Hint: give them more.