What is the definition of ventilation?

Ventilation refers to the process of moving air in and out of an indoor space, like a room or a building. It's super important because it helps to keep the air fresh and healthy for people to breathe. 

Here's how it works: when we breathe, we take in oxygen and release carbon dioxide. If the air in a room gets stale or has too much carbon dioxide, it can make us feel tired, dizzy, or even sick. Ventilation helps by bringing in fresh air from outside, which has plenty of oxygen, and pushing out the old, stale air. This exchange of air keeps things feeling comfortable and helps maintain good air quality.

There are different ways to ventilate a space. Natural ventilation uses openings like windows and doors to let fresh air in and let stale air out. Mechanical ventilation, on the other hand, uses things like fans and ducts to control the airflow. Sometimes buildings use a combination of both methods to make sure the air inside stays nice and fresh.

So, ventilation is all about keeping the air flowing so we can breathe easy and stay healthy!