When you connect a device that converts USB signals to Serial (UART), your operating system needs a driver to recognize it as a COM port. The "ser-setup" package typically contains:

: Always try to download drivers directly from official sources like WCH (for CH340) or Prolific (for PL2303).

: After installation, open Device Manager on Windows and look under "Ports (COM & LPT)" to ensure the device is correctly identified without a yellow warning triangle.

: Before extracting or running a .zip file from an unknown site, run it through an antivirus scanner.

: If you are using an Arduino clone or an ESP8266/ESP32 board, your computer likely won't "see" the board without these drivers.