Filtering is automated screening that blocks, hides, or suppresses content before it reaches a user. In security systems, filters can examine message source, rate, behavior, reputation, or content patterns and then allow, delay, or reject the item. The goal is to reduce noise and stop harmful or unwanted activity at the platform edge.
In cyber security, filtering matters because user trust depends on what gets through. Attackers often try to abuse notification channels, email, web forms, or messaging systems by sending repeated prompts, spam, or deceptive content until the channel loses credibility. Good filtering helps defend against that abuse by removing suspicious traffic early. In the Chrome notification context, filtering is what keeps abusive alerts from overwhelming users and preserving the value of legitimate notifications.