What is the function of the '->' in that line?

[NCEE]

I was going through a bit of open source code when I came upon this line
"pTerm = pid->pGain * error;"

What is the function of the '->' in that line?

 

[AlephZero]

pid is a pointer to a class or structure.
pGain is a member of the class or structure.
pid -> pGain means the same as (*pid).pGain (but it looks prettier).