The year 2023 represents fifty years since Hasegawa and Tappert predicted that temporally-localized solitons could be generated in optical fibers. This opened up an entirely new field of nonlinear fiber optics, and soliton concepts are now central to many different areas of photonics including the design of ultrafast lasers, frequency comb generation, as well as interdisciplinary studies related to rogue waves. This tutorial will provide an overview of the field.