A meeting is an event where two or more people come together to discuss one or more topics, often in a formal setting. Meetings can be held in person or virtually. They can be scheduled in advance or called on short notice.
An appointment is a scheduled time for a person to meet with another person or group of people. Appointments are usually made in advance and are often used for professional purposes.
A session is a period of time during which something happens. It can refer to a meeting, class, or other event that takes place over a period of time.
A class is a group of students who are taught together. Classes are usually held at regular intervals and are led by an instructor who teaches the students about a particular subject.
