Teletype Corporation's Model 33 terminal, introduced in 1963, was one of the most popular terminals in the data-communications industry. Over a half-million Model 32s and 33s were made by 1975, and the 500,000th was plated with gold and placed on special exhibit. Another 100,000 were made in the next 18 months, and Serial Number 600,000, manufactured in 1976, the United States Bicentennial year, was painted red-white-and-blue and shown around the United States during the last part of that year and the year after.