Media

Many medium

Human interaction(chat, relation, introduction)

SMS(info, require action, notice)

Phonecalls(quick, proxy)

Billboards(ubiquitous, eye can see)

Mails(letterbox, you are served)

Fax(copies)

Internet apps(unlimited)

Teleconference(facial, voice)

Television(remote surfing, couch potato)

Radio(leave it on)

Walkie-talkie(close community)

Pager(reception, operator)

Prints(always with you, availability)

Smoke signal(Red Indians)