Mathematics can be mastered by anyone who is interested in it. However, sometimes the interest comes later, or there is no opportunity at school to find interesting tasks. At the same time, mathematical knowledge is arranged in such a way that each subsequent level is based on the previous one. In order to give everyone the opportunity to try to master different mathematical techniques and ways of thinking, we decided to systematize mathematical knowledge in such a way as to help form an integral mathematical perspective from elementary school to the PhD examination. This system of knowledge will be filled consistently. We hope that our work will be useful and bring pleasure to all who want to learn to think critically.