A robocall is a phone call mass-dialed to large numbers of phone numbers using an auto-dialer system, playing pre-recorded voice messages. A single system can make thousands of calls per hour, making robocalls widely used for both legitimate purposes and abuse. In the United States, approximately 4-5 billion robocalls are made monthly, representing a serious global problem.
Legitimate uses include municipal disaster evacuation alerts, medical appointment reminders, school emergency contact networks, political party announcements during election periods, and bank fraud alerts. These are made with prior recipient consent or based on public interest.
However, abuse for fraud and illegal sales activities is a serious global problem. Typical techniques include recorded messages creating anxiety with "You have unpaid fees," "Your account will be frozen," or "Important notice from the tax office," then transferring to an operator via button press to extract personal information or money. Combined with caller ID spoofing to display bank or government numbers, these scams are increasingly common. In Japan, the Specified Commercial Transactions Act regulates unsolicited telemarketing calls.
When receiving a robocall, the response is to share no personal information once a recorded message plays and hang up immediately. Do not follow instructions like "Press 1 to connect to an operator" or "Press 9 to stop delivery." Pressing a button records your number as "active," leading to even more robocalls. Register the number for call blocking and enable spam call filters to prevent recurrence. The spread of the STIR/SHAKEN protocol is expected to advance robocall source verification. Review the latest countermeasures in robocall detection tips.