Man, mankind or people?

Traditionally, we use man to refer to all human beings, male and female, usually in contrast with other animals. However, many people consider this to be sexist, so it is better to use a different expression, such as human beings:

Human beings first emerged in Africa, some two million years ago. (preferred to Man first emerged …)

Mankind can also refer to all human beings, male and female, usually in the sense of social or conscious beings. Although people generally consider it less sexist than man, it is usually better to use a different expression, such as human beings (with a plural verb) or humankind (with a singular verb):

Human beings have always dreamt of happiness and of a perfect world. or Humankind has always dreamt of happiness … (preferred to Mankind has always dreamt …)

People can refer to all human beings, or to a group of persons in a particular situation. It is a plural noun and it takes a plural verb:

People will always need food, so the food industry will never disappear. (all human beings)

It’s difficult to sell an old computer. People don’t want second-hand ones. (those typical persons interested in buying computers)

People started coming into the hall at five-thirty, almost an hour before the start of the meeting. (those persons who were attending the meeting)