In a casino, what is the difference between a “dealer” and a “banker”?

I found an ad for a “casino banker gaming associate.” This position specifies that part of the associate’s responsibilities include:

Our opportunity requires working within a casino environment. The primary responsibilities include:

• Observing and participating in rotating bank games and verifying winning and losing bets;
• Providing excellent customer service to all participants; and
• Playing an optimal game strategy when it’s your turn to play.

Isn’t that what a dealer does? Can someone explain to me the difference between a “banker” and a “dealer” as it pertains to California casinos?