Hard-wired microphones are connected to a DI box, mixer or mixer amp via a connector cable. The most common interfaces are the ¼" jack plug or the male XLR connector, whilst computer microphones and inexpensive entry level models use a 1/8" mini-phone plug.
A relatively new type of microphone utilises a USB connector for recording directly onto PC hard drives using sampling software to accommodate "Pod casting" and audio blogs that can be posted to the internet.
Most PA mixer amps have the ability to connect both XLR and jack sockets, however, microphone inputs are normally clearly labelled on a mixer amp as they include the necessary electronic circuitry to deal with low level signals from microphones. As a rule of thumb these are generally 40 to 60Db lower than a standard line input so it is therefore important to know the gain differential between a mic and line input.