A ring group allows you to ring a collection of extensions in a variety of ring strategies. For example, you could put all of the technical support guys’ extensions in a ring group and call them one by one. Essentially, a ring group has a set of phone numbers or extensions that are bound together. Whenever a caller dials in, the auto-attendant transfers the call to that group, and all the phones ring simultaneously or sequentially (up to different ringing strategies).