hidden channel

- unit under test
- abrasive-cleaning unit
- absolute units
- acknowledgement signal unit
- acoustic units
- allocation unit
- angle-tracking unit
- Ångström unit
- answer-back unit
- answering unit
- antenna coupler unit
- anticoincidence unit
- arbitrary unit
- arithmetic unit
- arithmetic and logic unit
- assembly unit
- associative unit
- attached unit
- audio processing unit
- audio-response unit
- automatic calling unit
- automatic lock-on unit
- automatic range tracking unit
- auxiliary power unit
- balanced-armature unit
- balancing unit
- base station unit
- base station control unit
- basic display unit
- basic measurement unit
- basic processing unit
- beam steering unit
- best matching unit
- bistable unit
- break-contact unit
- bubble unit
- bubble storage unit
- buffer unit
- bus interface unit
- camera control unit
- capacitor-resistor unit
- card punch unit
- card punching unit
- card-reader unit
- cassette unit
- central processing unit
- certificate signing unit
- CGS units
- changeover-contact unit
- channel unit
- channel service unit
- channel service unit/digital service unit
- chrominance unit
- clock unit
- cluster unit
- coefficient unit
- coil-spring reverberation unit
- coincidence unit
- communications control unit
- competitive unit
- computer interface unit
- connectionist unit
- control unit
- control-display unit
- converter unit
- conveyorized drying unit
- crosstalk unit
- curve scanning unit
- data unit
- data-acquisition unit
- data-adapter unit
- data-collection unit
- data encryption unit
- data-handling unit
- data transfer unit
- delay unit
- derived units
- developer unit
- dialing unit
- differentiating unit
- digital reverberation-echo unit
- digital service unit
- digital storage unit
- discrete unit
- disk unit
- display unit
- driver unit
- dual processing unit
- electron unit
- ENIGMA duration unit
- ENIGMA virtual page unit
- execution unit
- expansion unit
- experimental unit
- failed unit
- failure unit
- fixed-head disk unit
- floating-point processing unit
- forming unit
- frequency identification unit
- fuel-cell unit
- function unit
- fundamental units
- GeForce graphics processing unit
- geometrical unit
- graphics processing unit
- hidden unit
- hidden-layer unit
- Horner unit
- imaginary unit
- inductive energy storage unit
- inertial measurement unit
- information unit
- in-order retirement unit
- input unit
- input/output unit
- inquiry unit
- instruction unit
- instruction fetch unit
- integrating unit
- interface unit
- internetwork unit
- interrogating unit
- I/O control unit
- LAN access unit
- language unit
- line terminal unit
- logical unit
- magnetic-core storage unit
- magnetic tape unit
- mains unit
- make-contact unit
- matching unit
- matrix unit
- maximum transmission unit
- measurement unit
- medium attachment unit
- memory unit
- memory management unit
- microcontrol unit
- microprocessing unit
- microprocessor unit
- microprocessor control unit
- microprocessor-controlled unit
- microprogrammed unit
- MKS units
- mobile TV unit
- modular unit
- motor unit
- movable-head disk unit
- multiple unit
- multiplier unit
- multiply/accumulate unit
- multipoint control unit
- multistation access unit
- near-eye unit
- nerve unit
- network interface unit
- neural-like unit
- neuromotor unit
- numeric processing unit
- observation unit
- off-line unit
- on-line unit
- orderwire unit
- output unit
- paged memory management unit
- parallel arithmetic unit
- perceptual unit
- peripheral unit
- peripheral interface unit
- peripheral processing unit
- permanent storage unit
- piezoelectric-crystal unit
- pluggable unit
- plug-in unit
- processing unit
- processor unit
- producer's desk unit
- program-control unit
- protected data unit
- protocol data unit
- prototype unit
- quartz-crystal unit
- radio channel unit
- random-access storage unit
- reader unit
- read-write unit
- receptor unit
- recording unit
- register, arithmetic and logic unit
- reproducing unit
- reserve unit
- resistor-capacitor unit
- response unit
- reverberation unit
- sample unit
- sampling unit
- satellite delay compensation unit
- secure access unit
- secure telephone unit
- self-contained unit
- semantic unit
- sensory unit
- serial arithmetic unit
- service unit
- service protocol unit
- shaker unit
- SI units
- six-head tape-loop echo-reverberation unit
- slide unit
- spare unit
- standby unit
- start unit
- stop unit
- storage unit
- summing unit
- system processing unit
- tape unit
- telecine unit
- terminal unit
- terminal-control unit
- terminal-interchange unit
- time-base unit
- time processor unit
- timing unit
- traffic unit
- translation unit
- transmission control unit
- trichromatic unit
- tuning unit
- turntable unit
- ultimate sampling unit
- visual display unit
- voice-response unit
- volume unit
- winning unit
- wire-stripping unit
- word-processing unit
- writing unit

- absolute code
- access code
- adaptive code
- additional code
- address code
- air-to-ground liaison code
- A-law code
- Alfa code
- alphanumeric code
- alternate mark inversion code
- AMI code
- answerback code
- area code
- assembly code
- authentication code
- authorization code
- automatic code
- auxiliary code
- balanced code
- bank code
- bar code
- Barker code
- base station identity code
- Baudot code
- BCD code
- BCH code
- binary code
- binary-coded decimal code
- biorthogonal code
- bipolar code
- bipolar with N-zero substitution code
- biquinary code
- block code
- BNZS code
- boot code
- bootstrap code
- Bose-Chaudhuri-Hocquenghem code
- break code
- brevity code
- BT code
- burst-correcting code
- burst-detecting code
- burst-trapping code - cable code
- cable Morse code
- call directing code
- call-station code
- capacitor color code
- card code
- carrier identification code
- chain code
- channel code
- character code
- circulant code
- close-packed code
- coarse acquisition code
- color code
- color bar code
- command code
- complementary code
- complementary Golay code
- completion code
- computer code
- computer numerical code
- concatenated code
- condensation code
- condition code
- constant-weight code
- Continental code
- control code
- convolution code
- convolutional code
- country code - cyclic code
- cyclic binary code
- decimal code
- decomposable Golay code
- dense binary code
- destination code
- device code
- diffuse code
- digital code
- direct code
- directing code
- dot-and-dash code
- double-adjacent error-correcting code
- drawing code
- DVD regional code
- EFM code
- EIA color code
- eight-level code
- eight-to-fourteen modulation code
- elaborated code
- electrical code
- electrical safety code
- entropy code
- equal-length code
- equidistant code
- equipment manufacturer code
- error code
- error-control code - escape code
- excess-three code
- executable machine code
- extended binary-coded decimal interchange-code
- extremal code
- feedback balanced code
- fieldata code
- firewall code
- five-level code
- fixed-length code
- fixed-weight code
- format code
- four-of-eight code
- four-out-of-eight code
- fractal code
- framing code
- full frame time code
- function code
- GBT code
- generalized burst-trapping code
- genetic code - group code
- Hamming code
- hidden codes - HSF code
- Huffman-Shannon-Fano code
- ID code
- identification code
- identity code
- inheritance code
- in-line code
- instruction code
- interchange code
- interlace code
- interleaved code
- International cable code
- international Morse code - interrupt code
- inverted code
- iterative code
- jargon code
- Java code
- key code
- lead color code
- legacy code
- line code
- linear code
- lock code
- longitudinal time code
- loop code
- machine code
- macro code
- magnetic tape code
- majority-decodable code
- make code
- Manchester code
- Manchester II code
- manipulation detection code
- manufacturer code
- maximally compressed pattern recognition code
- message authentication code
- Miller code
- minimum redundance code
- mnemonic code
- mobile country code
- mobile network code
- modular code
- Moore code
- Morse code
- Morse cable code
- multiple-address code
- multiple-burst code
- mutual code
- N-address code
- N-ary code
- native code
- nonprint code
- nonreturn-to-zero code
- nonreturn-to-zero inverted code
- NRZ code
- NRZI code
- object code
- offset binary code
- on-drop frame time code
- one-level code
- open source code - P-code
- p-code
- parity code
- parity-checking code
- partial-response code
- path-invariant code
- perfect code
- permutation code
- permutation-modulation code
- pilot code
- PN code
- polynomial code
- position code
- postal code
- precision code
- predictive code
- prefix code
- primary address code
- printer-telegraph code
- printing-telegraph code
- PRN code
- progressive code
- progressive/sequential code
- pseudonoise code
- pseudorandom noise code
- pseudo-ternary code
- public code
- pulse code
- punched-card code
- punched-tape code
- punctured code
- quasi-cyclic code
- quasi-perfect code
- quaternary code
- quinbinary code
- radar code
- radar-type code
- radio paging code N 1
- randomized code
- Read-Solomon code - redundancy-reducing code
- redundant code
- Reed-Muller code
- reenterable code
- reentrant code
- reflected binary code
- reflective code
- regional code
- relocatable code
- reserved code
- residue code
- resistor color code
- restricted code
- RETMA color code
- return code
- return-to-zero code
- RL code
- RMA color code
- robust code
- routing code
- run-length code
- RZ code
- salami code
- scan code
- search code
- secret code
- self-checking code
- self-complementing code
- self-correcting code
- self-documenting code
- self-dual code
- self-modifying code
- self-validating code
- sequential code
- servo code
- servo Gray code
- seven-unit teleprinter code
- SF code
- Shannon-Fano code
- shift codes
- short code
- signature code
- simplex code
- single-burst code
- SMPTE control code
- SMPTE time code
- source code
- spaghetti code
- specific code
- station-identification code
- stochastic code
- stop code
- straight-line code
- substitution error-correcting code
- synchronization error-correcting code
- systematic code
- systematic error-checking code
- tape code
- telegraph code
- teletype code
- teletypewriter code
- threaded code
- time code
- time address code
- time-invariant code
- transaction code - transparent code
- tree code
- trellis code
- twinned-binary code
- two-of-five code
- two-out-of-five code
- two-part code
- unbreakable code
- unipolar code
- unit disparity code
- unit-memory code - variable-length code
- variable-rate code
- Walsh code
- weighted code
- word code
- Wyner-Ash code
- zero-disparity code
- ZIP code
- zip code

- number of cylinders
- number of epochs
- number of heads
- number of hidden layers
- number of logical cylinders
- number of logical heads
- number of logical sectors
- number of primary turns
- number of quantizing levels
- number of secondary turns
- number of sectors per track
- number of sessions
- number of states
- number of tracks
- number of turns
- Abbe number
- absolute frame number
- abstract number
- account number
- additional quantum number
- algebraic number
- angular mode number
- assigned number
- Avogadro number
- axial mode number
- azimuthal quantum number
- base number
- Betti number
- binary number
- binary-coded decimal number
- block number
- Brinell hardness number
- bus number
- call number
- called directory number
- called terminal number
- calling directory number
- calling terminal number
- cardinal number - Cayley numbers
- channel number - cliquomatic number
- cluster number
- coded decimal number
- complex number
- composite number
- concrete number
- condition number
- controller number
- Conway number
- coprime numbers
- counting number
- customer number
- cutoff wave number
- cylinder number
- device number
- directory number
- double-length number
- double-precision number
- drive number
- effective number of bits - even number
- expected number of augmented doubles
- extension number
- f-number
- Fibonacci numbers
- fixed-point number
- floating-point number
- font number
- fractional number - Fresnel number
- function number - Grashof number
- groove number
- Gummel number
- Hartman number
- head number
- hexadecimal number - ID number
- identification number
- imaginary number
- infinite repeating decimal number
- inner quantum number
- interconnection level number
- international number
- Internet number
- internet number
- irrational number
- job number
- Julian number
- line number
- logical block number
- logical cylinder number
- logical device number
- logical head number
- logical sector number - Lorentz number
- fuzzy number
- L-R fuzzy number
- Lundquist number
- magic number
- magnetic quantum number
- magnetic Reynolds number
- main quantum number
- mass number
- maximum usable read number
- Mersenne prime numbers
- mixed number - multiple number
- natural number
- network number - normalized wave number
- Nusselt number
- occupation number
- odd number
- orbital quantum number
- ordinal number
- page number
- perfect number
- personal communication number - physical cylinder number
- physical head number
- physical sector number
- portable serial number - preprogrammed number
- prime number
- principal quantum number
- priority number
- propagation number
- pseudodecimal number
- pseudorandom number
- quantum number
- radial mode number
- radix number
- random number
- rational number
- read number
- read-around number
- real number - repeating decimal number
- resolvable element number
- revolution number
- Reynolds number
- round-off number
- scanning-lines number
- Schmidt number
- security service number
- seed number
- serial number
- Sherwood number
- signed number
- spin quantum number
- SS number
- statement number
- subnet number
- subscriber number
- surreal number
- T-number
- telephone number
- ticket number
- tolerant fuzzy number
- toll-free number
- total quantum number
- track number
- transcendental number
- transfinite number
- translational quantum number
- transverse wave number
- trapezoidal fuzzy number
- triangular fuzzy number
- unimodal fuzzy number
- unlisted phone number
- unsigned number
- version number
- vias number
- vibrational quantum number
- Vickers number
- volume reference number
- volume serial number
- wave number
- whole number
- winding number
- Wolf number

- absolute code
- access code
- adaptive code
- additional code
- address code
- air-to-ground liaison code
- A-law code
- Alfa code
- alphanumeric code
- alternate mark inversion code
- AMI code
- answerback code
- area code
- assembly code
- authentication code
- authorization code
- automatic code
- auxiliary code
- balanced code
- bank code
- bar code
- Barker code
- base station identity code
- Baudot code
- BCD code
- BCH code
- binary code
- binary-coded decimal code
- biorthogonal code
- bipolar code
- bipolar with N zero substitution code
- biquinary code
- block code
- BNZS code
- boot code
- bootstrap code
- Bose-Chaudhuri-Hocquenghem code
- break code
- brevity code
- BT code
- burst-correcting code
- burst-detecting code
- burst-trapping code
- C/A code
- cable code
- cable Morse code
- call directing code
- call-station code
- capacitor color code
- card code
- carrier identification code
- chain code
- channel code
- character code
- circulant code
- close-packed code
- coarse acquisition code
- color bar code
- color code
- command code
- complementary code
- complementary Golay code
- completion code
- computer code
- computer numerical code
- concatenated code
- condensation code
- condition code
- constant-weight code
- Continental code
- control code
- convolution code
- convolutional code
- country code
- cross-interleaved Read-Solomon code
- cue code
- cyclic binary code
- cyclic code
- decimal code
- decomposable Golay code
- dense binary code
- destination code
- device code
- diffuse code
- digital code
- direct code
- directing code
- dot-and-dash code
- double-adjacent error-correcting code
- drawing code
- DVD regional code
- EFM code
- EIA color code
- eight-level code
- eight-to-fourteen modulation code
- elaborated code
- electrical code
- electrical safety code
- entropy code
- equal-length code
- equidistant code
- equipment manufacturer code
- error code
- error detection and correction code
- error-control code
- error-correcting code
- error-detecting code
- error-locating code
- escape code
- excess-three code
- executable machine code
- extended binary-coded decimal interchange code
- extremal code
- feedback balanced code
- fieldata code
- firewall code
- five-level code
- fixed-length code
- fixed-weight code
- format code
- four-of-eight code
- four-out-of-eight code
- fractal code
- framing code
- full frame time code
- function code
- GBT code
- generalized burst-trapping code
- genetic code
- Golay sequential code
- Gray code
- group code
- Hamming code
- hidden codes
- high density bipolar code
- Hollerith code
- HSF code
- Huffman-Shannon-Fano code
- ID code
- identification code
- identity code
- inheritance code
- in-line code
- instruction code
- interchange code
- interlace code
- interleaved code
- International cable code
- international Morse code
- international standard recording code
- interrogation-code
- interrupt code
- inverted code
- iterative code
- jargon code
- Java code
- key code
- lead color code
- legacy code
- line code
- linear code
- lock code
- longitudinal time code
- loop code
- machine code
- macro code
- magnetic tape code
- majority-decodable code
- make code
- Manchester code
- Manchester II code
- manipulation detection code
- manufacturer code
- maximally compressed pattern recognition code
- message authentication code
- Miller code
- minimum redundance code
- mnemonic code
- mobile country code
- mobile network code
- modular code
- Moore code
- Morse cable code
- Morse code
- multiple-address code
- multiple-burst code
- mutual code
- N-address code
- N-ary code - nonreturn-to-zero code
- nonreturn-to-zero inverted code
- NRZ code
- NRZI code
- object code
- offset binary code
- on-drop frame time code
- one-level code
- open source code
- operation code
- order code
- P code
- parity code
- parity-checking code
- partial-response code
- path-invariant code
- p-code
- perfect code
- permutation code
- permutation-modulation code
- pilot code
- PN code
- polynomial code
- position code
- postal code
- precision code
- predictive code
- prefix code
- primary address code
- printer-telegraph code
- printing-telegraph code
- PRN code
- progressive code
- progressive/sequential code
- pseudonoise code
- pseudorandom noise code
- pseudo-ternary code
- public code
- pulse code
- punched-card code
- punched-tape code
- punctured code
- quasi-cyclic code
- quasi-perfect code
- quaternary code
- quinbinary code
- radar code
- radar-type code
- radio paging code N 1
- randomized code
- Read-Solomon code
- Read-Solomon product code
- recurrent code
- redundancy-reducing code
- redundant code
- Reed-Muller code
- reenterable code
- reentrant code
- reflected binary code
- reflective code
- regional code
- relocatable code
- reserved code
- residue code
- resistor color code
- restricted code
- RETMA color code
- return code
- return-to-zero code
- RL code
- RMA color code
- robust code
- routing code
- run-length code
- RZ code
- salami code
- scan code
- search code
- secret code
- self-checking code
- self-complementing code
- self-correcting code
- self-documenting code
- self-dual code
- self-modifying code
- self-validating code
- sequential code
- servo code
- servo Gray code
- seven-unit teleprinter code
- SF code
- Shannon-Fano code
- shift codes
- short code
- signature code
- simplex code
- single-burst code
- SMPTE control code
- SMPTE time code
- source code
- spaghetti code
- specific code
- station-identification code
- stochastic code
- stop code
- straight-line code
- substitution error-correcting code
- synchronization error-correcting code
- systematic code
- systematic error-checking code
- tape code
- telegraph code
- teletype code
- teletypewriter code
- threaded code
- time address code
- time code
- time-invariant code
- transaction code
- transfer authentication code
- transorthogonal code
- transparent code
- tree code
- trellis code
- twinned-binary code
- two-of-five code
- two-out-of-five code
- two-part code
- unbreakable code
- unipolar code
- unit disparity code
- unit-memory code
- Universal code
- universal product code
- variable-length code
- variable-rate code
- Walsh code
- weighted code
- word code
- Wyner-Ash code
- zero-disparity code
- ZIP code
- zip code

- Abbe number
- absolute frame number
- abstract number
- account number
- additional quantum number
- algebraic number
- angular mode number
- assigned number
- Avogadro number
- axial mode number
- azimuthal quantum number
- base number
- Betti number
- binary number
- binary-coded decimal number
- block number
- Brinell hardness number
- bus number
- call number
- called directory number
- called terminal number
- calling directory number
- calling terminal number
- card select number
- cardinal number
- Catalan's numbers
- Cayley numbers
- channel number
- ciphering key sequence number
- clique number
- cliquomatic number
- cluster number
- coded decimal number
- complex number
- composite number
- concrete number
- condition number
- controller number
- Conway number
- coprime numbers
- counting number
- customer number
- cutoff wave number
- cylinder number
- device number
- directory number
- double-length number
- double-precision number
- drive number
- effective number of bits
- electronic ID number
- enterprise number
- even number
- expected number of augmented doubles
- extension number
- f number
- Fibonacci numbers
- fixed-point number
- floating-point number
- font number
- fractional number
- frame number
- frequency-band number
- Fresnel number
- function number
- fuzzy number
- Ginsburg number
- Grashof number
- groove number
- Gummel number
- Hartman number
- head number
- hexadecimal number
- hopping sequence number
- host number
- ID number
- identification number
- imaginary number
- infinite repeating decimal number
- inner quantum number
- interconnection level number
- international number
- Internet number
- internet number
- irrational number
- job number
- Julian number
- line number
- logical block number
- logical cylinder number
- logical device number
- logical head number
- logical sector number
- logical unit number
- longitudinal propagation number
- Lorentz number
- Lundquist number - magnetic Reynolds number
- main quantum number
- mass number
- maximum usable read number
- Mersenne prime numbers
- mixed number
- mobile station international ISDN number
- mode number
- multiple number
- natural number
- network number
- non-registered parameter number
- normal fuzzy number
- normalized wave number
- number of augmented doubles
- number of cylinders
- number of epochs
- number of heads
- number of hidden layers
- number of logical cylinders
- number of logical heads
- number of logical sectors
- number of primary turns
- number of quantizing levels
- number of secondary turns
- number of sectors per track
- number of sessions
- number of states
- number of tracks
- number of turns
- Nusselt number
- occupation number
- odd number
- orbital quantum number
- ordinal number
- page number
- perfect number
- personal communication number
- personal identification number
- physical block number
- physical cylinder number
- physical head number
- physical sector number
- portable serial number
- portable user number
- Prandtl number
- preprogrammed number
- prime number
- principal quantum number
- priority number
- propagation number
- pseudodecimal number
- pseudorandom number
- quantum number
- radial mode number
- radix number
- random number
- rational number
- read number
- read-around number
- real number
- registered parameter number
- release number
- repeating decimal number
- resolvable element number
- revolution number
- Reynolds number
- round-off number
- scanning-lines number
- Schmidt number
- security service number
- seed number
- serial number
- Sherwood number
- signed number
- spin quantum number
- SS number
- statement number
- subnet number
- subscriber number
- surreal number
- T number
- telephone number
- ticket number
- tolerant fuzzy number
- toll-free number
- total quantum number
- track number
- transcendental number
- transfinite number
- translational quantum number
- transverse wave number
- trapezoidal fuzzy number
- triangular fuzzy number
- unimodal fuzzy number
- unlisted phone number
- unsigned number
- version number
- vias number
- vibrational quantum number
- Vickers number
- volume reference number
- volume serial number
- wave number
- whole number
- winding number
- Wolf number

- roughing mill group - absolute free group - absolute homotopy group - absolutely irreducible group - absolutely simple group - additively written group - adele group - adelic group - algebraically compact group - algebraically simple group - almost connected group - almost cyclic group - almost ordered group - almost periodic group - almost simple group - alternating form group - cancellative group - cellular homology group - characteristically simple group - complementing group - completely anisotropic group - completely discontinuous group - completely divisible group - completely indecomposable group - completely integrally closed group - deficient group - direct homology group - direct indecomposable group - doubly transitive group - finitely defined group - finitely generated group - finitely presented group - finitely related group - first homology group - first homotopy group - freely generated group - full linear group - full orthogonal group - full rotation group - full symmetric group - full unimodular group - group of classes of algebras - group of covering transformations - group of finite rank - group of infinite order - group of infinite rank - group of inner automorphisms - group of linear equivalence - group of linear forms - group of linear manifold - group of principal ideles - group of real line - group of recursive permutations - group of right quotients - idele class group - linearly ordered group - linearly transitive group - locally bicompact group - locally closed group - locally compact group - locally connected group - locally cyclic group - locally defined group - locally embeddable group - locally finite group - locally free group - locally infinite group - locally nilpotent group - locally normal group - locally solvable group - multiply primitive group - multiply transitive group - nonsolvable group - n-th homotopy group - ordered pair group - principal congruence group - properly orthogonal group - properly unimodular group - pure projective group - pure rotation group - pure simple group - quasipure projective group - quotient divisible group - residually nilpotent group - restricted holonomy group - sharply transitive group - simply ordered group - simply reducible group - simply transitive group - singular cogomology group - singular homology group - solvable group - stable group - strictly transitive group - strongly polycyclic group - subsolvable group - supersolvable group - totally ordered group - totally projective group - totally reducible group - triply transitive group - unitary symmetry group - unitary transformation group - value group - weak homology group - weakly mixing group