Although most researchers have a sense of what Open Science is, it is not easy to provide a clear-cut definition.
Open Science can be considered a movement or an approach to science that aims at making scientific research freely available to people within and outside of academics.
Its goal is to make science more accessible, reproducible and transparent.
Open science practices include pre-registration, replication research, sharing data and research tools, open peer-review, publishing open access, and open science evaluation and policies.
For an overview, see the Foster taxonomy: