We are a training practice, and so are involved in the training of both medical students and GP Registrars. You will always be asked beforehand if you mind if a student is present during your consultation, or if you are happy to see the registrar. Do not hesitate to say if you would prefer them not present.
Medical students are still undergoing their university training to become a qualified doctor, and are attached to the practice for short periods give them experience with real illnesses. They will generally be sat in with a qualified GP.
GP Registrars are fully qualified doctors who have had several years experience working in hospitals and are in the final stages of training to qualify as a GP. They are attached to the practice for 6 months to a year.