The DSB-S25 USB Serial Port is a USB-to-serial adapter, often used to connect older serial devices (like printers, modems, or industrial equipment) to a computer that lacks a traditional serial port (RS-232). The USB Serial Port driver allows the computer to recognize the adapter and use it as if it were a native serial port.
When you connect a DSB-S25 USB Serial Port to your computer, it will appear as a virtual COM port (such as COM1, COM2, etc.), allowing you to use legacy serial-based devices with modern PCs that typically lack physical serial ports.