strategies used by competitors to maximize the number of contacts made and multipliers earned. Some stations and operators specialize in certain contests, and either rarely operate in others, or compete in them with less seriousness. As with other sports, contest rules evolve over time, and rule changes are one of the primary sources of controversy in the sport. History of contesting The origin of contesting can be traced to the Trans-Atlantic Tests of the early 1920s, when amateur radio operators first attempted to establish long distance radiocommunications across the Atlantic Ocean on the short wave amateur radio frequencies. Even after the first two-way communications between North America and Europe were established in 1923, these tests continued to be annual events at which more and more stations were successful in establishing two-way contacts over greater and greater distances. In 1927, the American Radio Relay League, which had been principal in organizing and publicizing these tests, proposed a new format for the annual event, encouraging stations to make as many two-way contacts with stations in other countries as possible. The 1928 International Relay Party, as the event was renamed, was the first organized amateur radio contest. The International Relay Party was an immediate success, and was sponsored annually by the ARRL from 1927 through 1935. In 1936, the contest name changed to the ARRL International DX Contest, the name under which it is known today. To complement the burst of activity and interest being generated in DX communications by the popularity of the International Relay Parties, the ARRL adopted a competitive operating format for events designed for non-international contacts. The first ARRL All-Sections Sweepstakes Contest was started in 1930. The Sweepstakes required a more complicated exchange of information for each two-way contact that was adapted from the message header structure used by the National Traffic System. The competition was immediately popular, both with those operators active in the NTS who participated as an opportunity to gauge the merits of their station and operating skills, and among those for whom the competitive excitement of the event was the primary attraction. The contest, sponsored annually by the ARRL, became known as the ARRL November Sweepstakes in 1962. Another important innovation in early contesting was the development of Field Day operating events. The earliest known organized field day activity was held in Great Britain in 1930, and was soon emulated by small events through Europe