A more thorough explanation:

A glass ceiling is a term used to describe an invisible barrier that prevents certain groups of people, especially women, from advancing in their careers due to discrimination.

For example, a woman may be qualified for a promotion, but she is passed over for a male colleague who is less qualified. This is because of the belief that women are not as capable as men in certain roles, which is a form of discrimination.

Another example is when a woman is paid less than a man for doing the same job. This is also a form of discrimination and can prevent women from advancing in their careers.

The term "glass ceiling" is used to describe this phenomenon because it is an invisible barrier that is difficult to see, but it is very real and can be very damaging to those who are affected by it.