TELECOMMUNICATIONS DEVICE FOR THE DEAF

Domain	Definition
Computing	Telecommunications Device for the Deaf (TDD) A terminal device used widely by deaf people for text communication over telephone lines. The acronym TDD is sometimes expanded as "Telecommunication Display Device" but is generally considered to be derived from "Telecommunications Device for the Deaf", although there is some disagreement on this. The deaf themselves do not usually use the term "TDD", but prefer simply "TTY" -- possibly the original term. The ambiguity between this and the other meanings of "TTY" is generally not problematic. The acronym "TTD" is also common [Teletype for the deaf?]. The standard most used by TDDs is reportedly a survivor of Baudot code implemented asynchronously at 45.5 or 50 baud, 1 start bit, 5 data bits, and 1.5 stop bits. This is generally incompatible with standard modems. [Standards docs? i18n issues?] A typical TDD is a device about the size of a small laptop computer (resembling, in fact, a circa 1983 Radio Shack Model 100 computer) with a QWERTY keyboard, and small screen (often one line high, often made of an array of LEDs). There is often a small printer for making transcripts of terminal sessions. Because of the Stone Age vintage of this technology (the idiosyncrasy of which drives up the expense of individual units), it is thought that TDD standards should transition to use of standard modem line settings (e.g., ASCII 2400-8-N-1). An obstacle to this is the millions of Baudot-only terminals in use (an example of lock-in with a high cruft factor). Another scenario sees the use of TDDs being replaced by the use of personal computers and talk protocols, presumably over the Internet. (1998-06-15). Source: The Free On-line Dictionary of Computing.
Source: compiled by the editor from various references; see credits.

Hexadecimal (or equivalents, 770AD-1900s) (references)

54 45 4C 45 43 4F 4D 4D 55 4E 49 43 41 54 49 4F 4E 53 44 45 56 49 43 45 46 4F 52 54 48 45 44 45 41 46

Leonardo da Vinci (1452-1519; backwards) (references)

Binary Code (1918-1938, probably earlier) (references)

01010100 01000101 01001100 01000101 01000011 01001111 01001101 01001101 01010101 01001110 01001001 01000011 01000001 01010100 01001001 01001111 01001110 01010011 00100000 01000100 01000101 01010110 01001001 01000011 01000101 00100000 01000110 01001111 01010010 00100000 01010100 01001000 01000101 00100000 01000100 01000101 01000001 01000110

HTML Code (1990) (references)

&#84 &#69 &#76 &#69 &#67 &#79 &#77 &#77 &#85 &#78 &#73 &#67 &#65 &#84 &#73 &#79 &#78 &#83 &#32 &#68 &#69 &#86 &#73 &#67 &#69 &#32 &#70 &#79 &#82 &#32 &#84 &#72 &#69 &#32 &#68 &#69 &#65 &#70

ISO 10646 (1991-1993) (references)

0054 0045 004C 0045 0043 004F 004D 004D 0055 004E 0049 0043 0041 0054 0049 004F 004E 0053 0044 0045 0056 0049 0043 0045 0046 004F 0052 0054 0048 0045 0044 0045 0041 0046

Encryption (beginner's substitution cypher): (references)

TELECOMMUNICATIONS DEVICE FOR THE DEAF

Specialty Definition: TELECOMMUNICATIONS DEVICE FOR THE DEAF

Computing

Crosswords: TELECOMMUNICATIONS DEVICE FOR THE DEAF

Alternative Orthography: TELECOMMUNICATIONS DEVICE FOR THE DEAF

54 45 4C 45 43 4F 4D 4D 55 4E 49 43 41 54 49 4F 4E 53 44 45 56 49 43 45 46 4F 52 54 48 45 44 45 41 46

&#84 &#69 &#76 &#69 &#67 &#79 &#77 &#77 &#85 &#78 &#73 &#67 &#65 &#84 &#73 &#79 &#78 &#83 &#32 &#68 &#69 &#86 &#73 &#67 &#69 &#32 &#70 &#79 &#82 &#32 &#84 &#72 &#69 &#32 &#68 &#69 &#65 &#70

0054 0045 004C 0045 0043 004F 004D 004D 0055 004E 0049 0043 0041 0054 0049 004F 004E 0053 0044 0045 0056 0049 0043 0045 0046 004F 0052 0054 0048 0045 0044 0045 0041 0046

543946393749474755484337355443494853238395643373924049522544239238393540

INDEX