Share what you know, what you have experienced, what you have done before, what you have studied, share freely with others. As long as you are not sharing confidential, private or proprietary information, share what you know in service of helping other people.
While many see hoarding information as a chip they may want to cash in at a later date as something that provides them with “job security” – I see it differently. I see those who refuse to share info and help their colleagues as a liability, as someone who is self-centered and only cares about themselves and their short-term goals. In the end, if they are not team players, perhaps they shouldn’t be on a team.