On the occasion of the 50 years since the launch of Helios 1 and Helios 2, we proposed a special collection related to the solar wind, its origin, evolution, and space weather related effects. In addition to old missions like ULYSSES that explored the solar wind outside the ecliptic plane, recent missions like the Parker Solar Probe (PSP) and Solar Orbiter (SolO), as well as established ones such as the Solar Dynamics Observatory (SDO) and the Solar Terrestrial Relations Observatories (STEREOs), offer extensive new measurements that help to refine existing knowledge of slow and fast solar wind in the heliosphere and the development of new models. This collection addressed different solar wind topics, which included but were not limited to the mechanisms of solar wind acceleration and outflow, dynamics of stream interaction, the configuration of the magnetic field and plasma topology at the source surface and within the inner heliosphere.