If you are holding a live auction for instance or an event in a public area (a mall perhaps?) or outdoors you will have different needs.
There are three basic types of wireless microphones – Lapel clip-on, handheld and headset.
Wired microphones are normally the handheld variety but they can be inserted into a stand for tabletop or floor use.
A special type of microphone known as a condenser microphone is typically used on a podium. It is a high gain microphone and well suited for picking up voices of people who are untrained in microphone use or that stand too far away from a traditional microphone to be heard.
Condenser microphones are also well-suited for picking up groups of people such as choirs or panelists.