TTYs are telephone/machines that look like a small electronic typewriter with an LED screen readout. The equipment is connected to the telephone system through a standard telephone jack, and must also be plugged into an electrical outlet to operate the LED readout. TTYs can be used by hard of hearing or deafened people to communicate directly with each other by typing if both parties have the equipment. As well, Manitoba Telecom Services (MTS) operates the Manitoba Relay Service (MRS), to enable communication between the hearing world and hard of hearing or deafened people through specially trained operators. The service enables a hard of hearing or deaf person to read verbal messages, as the MTS operator types the speaker’s words into the system for display on the receiving TTY screen. The MRS system includes Voice Carry Over (VCO) service, which allows the TTY user to reply by speaking into the telephone (the other party hears the voice directly), or by typing a reply, which the operator then reads to the other party.