A ring tone is the sound made by a telephone to indicate an incoming call. The term, however, is most often used to refer to the customizable sounds available on mobile phones. This facility was originally provided so that people would be able to determine when their phone was ringing when in the company of other mobile phone owners. A phone only rings when a special "ringing signal" is sent to it. For regular telephones, the ringing signal is a 90-volt, 20-hertz, AC wave generated by the switch to which the telephone is connected. For mobile phones, the ringing signal is a specific, radio-frequency signal. The rise of video games has also contributed to the popularity of ring tones.[1] On August 5, 2006, the BBC reported that "free ringtones" was the eighth most likely search term to return links to malware. Ringtone formats eMelody - Older Ericsson format. iMelody - Most new phones that don't do Nokia's Smart Messaging are using this format. kws - Kyocera's ringer format. mid / midi - Popular sound format. morse code - Text files with a .morse extension get converted into morse code songs mot - And older ringer format for Motorola phones. Newer Motorola do iMelody I believe. nokia / sckl / ott - Nokia Smart Messaging format. Nokia phones can receive ringtones as a text message. Ringtone tools can create these text messages. This allows anyone with a compatible phone to load their own ringtones in without a datacable. There are other phones besides Nokia that use this. pdb - Palm database. This is the format used to load ringtones on PDA phones such as the Kyocera 6035 and the Handspring Treo rtttl - A popular text format for ringtones. rtx - Similar to rtttl with some advanced features. Also the octaves are different on rtx. samsung1 & samsung2 - Samsung keypress format. siemens keypress - Can create and read in a Siemens text file format. siemens SEO - Siemens SEO binary format.