Radiomics is a new concept that has been functioning in medicine for only a few years. This idea, created recently, relies on processing innumerable quantities of metadata acquired from every examination, followed by extraction thereof from relevant imaging examinations, such as computer tomography (CT), magnetic resonance imaging (MRI), or positron emission tomography (PET) images, by means of appropriate created algorithms. The extracted results have great potential and broad possibilities of application. Thanks to these we can verify efficiency of treatment, predict locations of metastases of tumours, correlate results with histopathological examinations, or define the type of cancer more precisely. In effect, we obtain more personalised treatment for each patient, which is extremely important and highly recommendable in the tests and applicable treatment therapies conducted nowadays. Radiomics is a non-invasive and high efficiency post-processing method. This article is intended to explain the idea of radiomics, the mechanisms of data acquisition, existing possibilities, and the challenges incurred by radiologists and physicians at the stage of making diagnosis or conducting treatment.