Field Day is a nationwide celebration of the capability of radio amateurs to help out in crises by providing emergency communications.  Over a two-day period large teams of hams set up their equipment,

communicate with as many as possible other amateur stations, and finish by dismantling and storing equipment for next year.  To be sure Field Day is a hard fought competition, in the strategizing, in the planning, and in the field.  But beyond

competition, it is the best opportunity available to new hams to learn equipment set-up and operation. The lessons learned can be applied not just to FD, but also to home stations, ARES, and special events relying on local communicators.

The event is organized by the American Radio Relay League (ARRL), and over 1200 groups in the United States participate.   Field Day was initiated in 1933.