A type of modem that relies on a computer's CPU, software, and the Windows operating system to work. Winmodems are known to be system resource hogs, and usually come with buggy drivers causing system instability.
Though Winmodems are intended to be used with the Windows operating system, there are Linux drivers available. Regardless of what you may read or hear, Winmodems are not real modems.
Controller-based modems are superior to Winmodems because they don't rely on your computer's CPU or operating system to work.