Amateur radio , also known as ham radio , is the use of radio frequency spectrum for purposes of non-commercial exchange of messages, wireless experimentation, self-training, private recreation, radiosport , contesting , and emergency communication. The term "amateur" is used to specify "a duly authorised person interested in radioelectric practice with a purely personal aim and without pecuniary interest;"  either direct monetary or other similar reward and to differentiate it from commercial broadcasting , public safety such as police and fire , or professional two-way radio services such as maritime, aviation, taxis, etc. The amateur radio service amateur service and amateur-satellite service is established by the International Telecommunication Union ITU through the Radio Regulations. National governments regulate technical and operational characteristics of transmissions and issue individual stations licenses with a unique identifying call sign , which must be used in all transmissions.
Amateur sports - Wikipedia
A common misconception about amateurs and professionals is that professionals are paid to play sports whereas amateur athletes are not. Amateur athletes often receive some compensation for their efforts. In ancient Greece, for example, victorious athletes in the Olympics were handsomely rewarded for their efforts. As of the early s many college athletes receive academic scholarships for playing on a college team.
Amateur sports are sports in which participants engage largely or entirely without remuneration. The distinction is made between amateur sporting participants and professional sporting participants, who are paid for the time they spend competing and training. In the majority of sports which feature professional players, the professionals will participate at a higher standard of play than amateur competitors, as they can train full-time without the stress of having another job. The majority of worldwide sporting participants are amateurs. Sporting amateurism was a zealously guarded ideal in the 19th century, especially among the upper classes, but faced steady erosion throughout the 20th century with the continuing growth of pro sports and monetisation of amateur and collegiate sports, and is now strictly held as an ideal by fewer and fewer organisations governing sports, even as they maintain the word " amateur " in their titles.
Purpose: To compare the return-to-play rates, patient-reported outcome PRO scores, and satisfaction between high-level amateur athletes and recreational athletes and to evaluate for differences in ability to return to sport in these groups based on patient-related and sport-related characteristics. Athletes were classified as high-level amateur or recreational. Athletes were also divided into 6 distinct sporting categories based on the physical demands on the hip.