Could you explain triangulation to me?

[Kimasxi]

Hello, I watched Teal Swan's explanation of triangulation manipulation and unfortunately it is too difficult to me to comprehend
I got lost at the moment when she said "PERSON B then becomes a carrier of that conflict between PERSON A and PRESON C" - I don't understand what happens there. Could you may be give me some examples?
 

What person A managed to do until that point is to make person C go to person B to defend person A against B, right?  What happens now?