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What is TTY?

Mary McMahon
Mary McMahon
Mary McMahon
Mary McMahon

A TTY is a telephone which is specially outfitted for users who are deaf or hard of hearing. The term stands for “teletypewriter,” and it is sometimes used to describe teletypes in general. TTY systems allow people who are deaf and hard of hearing to make calls to each other, and with the assistance of relay systems, users can also communicate with people who do not have these systems.

Essentially, a TTY system allows the user to place a phone call and then communicate through written text, rather than spoken communication. Systems include a telephone handset that is attached to a keyboard; each key makes a specific tone that can be read by the handset. The handset communicates those tones to a receiver on the other end of the line, and the receiver interprets the tones and generates a line of text.

A TTY can help people who are deaf or hard of hearing.
A TTY can help people who are deaf or hard of hearing.

Obviously, when someone places a call with a TTY system, they need to be certain that the recipient also has one. If the recipient has no TTY receiver, he or she will pick up the phone and hear a series of tones. In a situation where someone with a system needs to call someone without one, or vice versa, a telephone relay service is used. The relay service can read typed messages to callers who can hear, and turn spoken messages into text for deaf and hard of hearing callers.

Teletype users are expected to be able to type quickly and accurately.
Teletype users are expected to be able to type quickly and accurately.

Because most people can potentially speak much more quickly than they can type, TTY systems can be very clumsy. Frequent users typically develop a set of abbreviations, such as “GA” for “go ahead” to indicate that someone is done typing, or “sk” for “stop keying,” indicating that someone plans to end the conversation. People also heavily abbreviate words rather than writing them out to make the conversation go more quickly, and they tend to use TTY systems for quick communications rather than leisurely chats.

'TTY' stands for teletypewriter.
'TTY' stands for teletypewriter.

The main problem with TTY systems is that users must be able to type rapidly and accurately. Some deaf and hard of hearing users are also accustomed to using sign language, which has a different grammatical system than the written English language. This can cause some confusion when using a TTY system. Systems also rely on things like flashing lights or vibration to alert deaf and hard of hearing users to incoming calls, and it is possible to miss a call if someone only lets the phone ring a few times, which can be very frustrating.

Mary McMahon
Mary McMahon

Ever since she began contributing to the site several years ago, Mary has embraced the exciting challenge of being a WiseGEEK researcher and writer. Mary has a liberal arts degree from Goddard College and spends her free time reading, cooking, and exploring the great outdoors.

Learn more...
Mary McMahon
Mary McMahon

Ever since she began contributing to the site several years ago, Mary has embraced the exciting challenge of being a WiseGEEK researcher and writer. Mary has a liberal arts degree from Goddard College and spends her free time reading, cooking, and exploring the great outdoors.

Learn more...

Discussion Comments

MissDaphne

@SherylJones - I don't think you do need and landline or special TTY machines; I think there are cell phones you can use. CNET, for instance, will let you search for reviews of TTY-compatible cell phones.

I have only once received a call from a TTY relay service. It was actually really disorienting; neither the relay operator nor the person calling really explained what was happening, so it was hard for me to figure out what was going on (I did after a minute or two, naturally). This was at a job I had once where I was taking phone calls for job applicants.

Maybe TTY relay operators should have a standard spiel that they can use for call recipients who are not familiar with the technology. But this was several years ago, so maybe now they do? Or maybe I just had a particularly awkward experience.

I do wonder to what extent TTY will continue to be a technology that's commonly used by the deaf and hard of hearing now that so many people have a device in their pockets that does something similar - a cell phone capable of text messaging!

SherylJones

Is it necessary to have a landline in order for TTY to operate?

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    • A TTY can help people who are deaf or hard of hearing.
      By: Voyagerix
      A TTY can help people who are deaf or hard of hearing.
    • Teletype users are expected to be able to type quickly and accurately.
      By: ViewApart
      Teletype users are expected to be able to type quickly and accurately.
    • 'TTY' stands for teletypewriter.
      'TTY' stands for teletypewriter.
    • Acoustic couplers -- which send and receive computer data through telephone lines -- are built into many types of telecommunications devices used by the deaf.
      Acoustic couplers -- which send and receive computer data through telephone lines -- are built into many types of telecommunications devices used by the deaf.