Google hires bright, curious people from many different fields who are all united by wanting to do cool things that matter.
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This will differ from team to team. However most managers are highly accessible and you can walk over to their desk to talk at any time. Some are better mentors than others, some are more technical focused, others are more career focused. They are generally on your side and want you to succeed. If you're unhappy with your manager's approach then you can talk to them about this.