Do we use majority/minority with people only?

Majority means large number and minority means small number.

Is this example correct?
The majority of men work in army / The minority of women work in army.

I have to teach my students the difference of these two words with some examples. Please clarify these two words with more examples and the way I should teach them for better understanding.

Not only people, Meg. The two words have several meanings and uses, but in the sense you are speaking of, 'majority' is a subgroup which is greater than 50% ('most') of the total group, while 'minority' is a subgroup which is less than 50% of the total group. The concept of being part of a total group is important.

For instance, your examples-- 'the majority of men work in army / The minority of women work in army'-- do not make real sense, because we don't know how the rest of the men and women are associated with these statements.

The majority of soldiers are men and the minority of soldiers are women. (= most soldiers are men, not women)

I spend the majority of my waking time at my computer. (= I spend little time away from this machine)

Women truck drivers are in the minority in my country. (= most truck drivers are men; few are women)

The majority of the books in my library are language-related, while a minority of them are novels.

In each sentence, we can understand what the total group is, from which the minority and majority emerge.

Does this help?
Really very clear explanation!

I used to think that we use these terms only for people.

I am supposed to teach the difference between these two words by drawing some stick figures on the board. I think now it is very easy for me to draw the books' example given by you and explain the terms to my students.

Thank you very much for your help!