The rule titled 'High Volume of Bytes Out to Url' aims to detect unusually high outbound web traffic, specifically over 1GB of data sent to a single URL within a two-minute interval. It employs the Web data model to aggregate the total bytes sent out, focusing on identifying potential data exfiltration activities that might be attributable to malware or malicious insiders. This detection is critical as it flags behaviors that could result in unauthorized data transfers, ultimately leading to data breaches and compromises of sensitive information. In case of confirmation of malicious behavior, immediate investigation is emphasized to assess the legitimacy of the outbound data and mitigate any risks posed by such transfers.