What job is to keep watch and give warning of danger?

The job of keeping watch and giving warning of danger is often associated with a "sentinel" or "watchman." These roles involve monitoring a specific area for potential threats and alerting others when danger is detected. This can be found in various contexts, such as security personnel in buildings, military sentries, or even lifeguards at a beach. Their primary responsibility is to ensure safety and provide timely warnings to prevent harm.