These microphones are designed for use within conference environments. They will connect to your Digital Voice Recorder and allow you to record a number of people at one time. They generally have specific features designed for use in conferencing.
For Example, the new Olympus ME-33 has Omni- Directional Microphone Pick-up and supports Daisy Chaining allowing up to 6 additional microphones to be added in order to pick up a large number of attendees within a conference. With its Solid Rubber Base and slim design it makes this product ideal to place on large conference tables.