Professional - Takes part in the sport as a full-time job and they get paid for taking part
Amateur - Pastime or hobby rather than for financial gain. Usually have a job alongside it
Semi-professional - combination of the two above. Usually have another job but also get paid for taking part. Some work art-time so they can train and play for a longer period of time.
Loopholes that enable the amateur or 'shamateurs' to receive money:
Sponsorship deals - performer is given equipment, clothing and training facilities and cash payment for endorsing a product
Occupations - a 'job' that enables performers to have time off to train and compete
Scholarships - universities and colleges have these to allow full-time sport to be carried out
PE teacher, Coach, Trainer, Physiotherapist, sports management or personal trainer