A gatekeeper is an actor or influencer who significantly influences the public decision-making and opinion-forming process. Through its effect on public perception, it contributes to the fact that certain views, information or positions are adopted or supported by a large part of the population. Gatekeepers are often individuals or institutions with high social credibility and reach. Especially through social media and blogs, the role of the gatekeeper has changed in the past years, so that today basically every person with the appropriate reach and influence can take on this function.