Analogue:  

In telephone transmission, spoken words are transmitted as analogue sound waves or frequencies (as opposed to digital signals). Until the late 1960s, all telephone calls were analog. Now, while most phone companies are digital, there are still many sections of telephone networks that use analogue service, including the majority of home telephones that plug into jacks and the telephone lines from homes to the nearest phone company equipment. Modems broaden analogue capabilities, allowing these lines to carry data from digital computers.