- Unaddressed printed matter
- Addressed printed matter
- Standard letter
- Press advertising with order form
- Catalogue
- Telephone with human intervention
- Telephone without human intervention (automatic calling machine, audiotext)
- Radio
- Videophone (telephone with screen)
- Videotex (microcomputer and television screen) with keyboard or touch screen
- Electronic mail
- Facsimile machine (fax)
- Television (teleshopping).