What is discrimination and where does it come from?  

According to the dictionary

1.

the unjust or prejudicial treatment of different categories of people or things, especially on the grounds of race, age, or sex.

"victims of racial discrimination"

recognition and understanding of the difference between one thing and another.

"discrimination between right and wrong"

2.

recognition and understanding of the difference between one thing and another.

"discrimination between right and wrong"

(Oxford Languages) 

 

Article in the American Psychological Association

Discrimination: What it is, and how to cope

https://www.apa.org/topics/racism-bias-discrimination/types-stress