Voicemail is something almost all Americans are familiar with these days. One of the best descriptions of what all voicemail can encompass is reprinted below from the Wikiedpia.

Voicemail (or voice mail; abbreviated v-mail or vmail) is a centralized system of managing telephone messages for a large group of people. In its simplest form it mimics the functions of an answering machine, but uses a centralised server rather than equipment at the individual telephone. Most Voice Mail systems are more sophisticated than answering machines, with the ability to forward messages to another voice mailbox, send messages to multiple voice mailboxes, add voice notes to a message, store messages for future delivery, make calls to a telephone or paging service when a message is received (outcall, SMS, MMS, e-mail, etc. notification), transfer callers to another phone for personal assistance and play different message greetings to different callers. Voicemail messages are stored in media used by computers to store other forms of data (hard drives, optical drives, and tape).

Many voicemail systems also offer an automated attendant facility, allowing callers answered by the system to dial a selected person's mail box or telephone.

Voicemail systems are found associated with many office telephone systems or PBX. They may also be associated with public telephone lines as network services. Mobile phones generally have voicemail as a standard network feature. The most modern implementation of voicemail are support fax, voicemail to text services, which transform each incoming voice message into text messaging for immediate delivery of a readable copy to SMS, MMS, alphanumeric pager, and e-mail.