How Pimples Form
The yellow liquid is called Sebacecus Gland but also called Sebum. This is in your pores.
Bacteria loves to feed on Sebum. So it does so and causes an infection.
Your white blood cells try to fight off the infection but instead pile up on each other.
Eventually your white blood cells cause inflamation and cause your pimple to be present on your face.
When you pop the pimple with your fingers, another one can appear on your face, in the exact same spot where you popped it because when you do that, the bacteria on your hands can get into your pores.
Facts about pimples
Acne is common
Sun exposure can reduce breakouts.
Chocolate does not cause pimples to form
Acne can occur at any age.
Exercise can make acne worse.