A jack is similar to a port and is a hole or other connection that allows a compatible plug to connect into the jack. You always plug something into a jack and today the term is often used when describing an audio jack. In the picture is an example of three mini-plug audio jacks.

Examples of audio jacks

  • Microphone jack
  • Sound in and Line in
  • Sound out and Line out

Female connector, Hardware terms, Port

  • What is the difference between a connector, jack, plug, and port?
  • Sound card help.