Simplify the following text for a Grade 14 native English-speaking person.
Original: Wind speeds usually mean the movement of air in an outside environment , but the speed of movement of air inside is also important in many cases , including weather forecasting , aircraft and maritime operations , construction and civil engineering .
Simplified: Wind speed has always meant the movement of air in an outside environment , but the speed of air movement inside is important in many areas , including weather forecasting , aircraft and maritime operations , building and civil engineering .