The 1968 influenza pandemic was a time when many people in the world caught H3N2 influenza A and became sick. It was also called Hong Kong flu in Western countries because Westerners first noticed it when it was in Hong Kong. It spread through the whole world. It killed 1 million people.
Organization is the idea of putting things together in a logical order. The verb is "to organize".
An organization is a group of people who work together. Organizations exist because people working together can achieve more than a person working alone.
To make sure people work together, organizations usually have leaders.