Text-to-Speech. The flip side of speech recognition, TTS takes written words and converts them to speech. Thus, when a caller requests specific information from a voice portal, such as driving directions, TTS reads the directions to the caller. Early TTS efforts were slow and were usually read by a computerized voice that was often referred to as “Igor” because of its similarity to the voice of the character of the same name in old horror movies. Current TTS technology is much more natural sounding, and in some situations the caller would be challenged to differentiate TTS from an actual human speaker.