Before revision: The first edition of WED in 2019, as well as the following ones, were based on the concept of holding simultaneous online and on-site celebrations, hosted by UNESCO, WFEO, engineering institutions members of WFEO, as well as generating social media trends and message on the theme of event, engaging with UN agencies such as URL One Earth|date=March 4, 2022||website=Sunday Observer , corporate bodies, other associations, media and students.
After revision: The first edition of WED in 2019, as well as the following ones, were based on the concept of holding simultaneous online and on-site celebrations, hosted by UNESCO, WFEO, engineering institutions members of WFEO, as well as generating social media trends and message on the theme of event, engaging with UN agencies such as UNEP , corporate bodies, other associations, media and students.