A receptacle that can detect the insertion and extraction of a plug includes: a receptacle shell having formed therein a plug insertion port into which the plug is inserted and from which the plug is extracted; a receptacle body provided inside the receptacle shell; a movable contact that is installed at a base portion of the receptacle body, the base portion faces a distal end of the plug inserted into the plug insertion port, and that is deformed elastically when pushed by the plug; and an immovable contact that is installed at the base portion, is normally spaced from the movable contact, and comes into contact with the movable contact when the movable contact is pushed by the plug and elastically deformed. The receptacle that can conform to the HDMI standard can be realized without adding any modification to main components relating to mating with a plug.