if and only if; used to show that the predicate that follows it has the same truth value as the predicate that precedes it
Identify Friend or Foe - a system for electronically differentiating between friendly and enemy aircraft
A system using radar transmission to which equipment carried by friendly forces automatically responds by emitting a unique characteristic series of pulses thereby distinguishing themselves from enemy forces It is the "Mode IV" for the aircraft transponder See also transponder
Identification Friend or Foe Electronic equipment that sends an encoded digital signal containing identification data by radio
Abbreviation of "if and only if", which designates material equivalence See equivalence, material
Read "if-and-only-if" This is the relation of logical equivalence, often used in defining terms 'p if q' allows for the possibility that p is true without q being true; 'p iff q' discounts this possibility
Identification Friend/Foe Term given to systems designed to prevent 'friendly fire' incidents, either by warning or by actual weapon lock out
The image file format was originally created for the Amiga but can now be read by numerous different image manipulation programs for several different platforms
Interchange File Format A very flexible format generally used on the Amiga Sound samples are generally stored as a subset of IFF called 8SVX 8SVX can only store 8bit mono samples - it can hold the sample rate but very few programs that can save 8SVX samples actually do this J K L
Electronic Arts' Interchange File Format, and is the image format used by Amiga and Atari ST personal computers There are multiple IFF formats, the most popular are the image and sound files A file with the IFF suffix may, therefore, be a sound, not a picture - and it might be any one of a number of other types of data IFF images may rarely have the suffix ILBM, for InterLeaved BitMap, or just LBM on DOS-based systems IFF pictures are not at all efficient, spacewise, but they're fast to display, which was important for poor little Amigas with a 0 7 million instruction per second (MIPS) processor With current PCs steaming along at hundreds and hundreds of MIPS, this no longer matters at all All IFF images can be compressed or uncompressed; just about all are compressed The compression, like the whole format, is built for speed, not efficiency, and so doesn't reduce the size much J Return to top