delta

n. 1. [techspeak] A quantitative change, especially a small or incremental
one (this use is general in physics and engineering). I just doubled the
speed of my program! What was the delta on program size? About 30 percent.
(He doubled the speed of his program, but increased its size by only 30
percent.) 2. [Unix] A diff , especially a diff stored under the set of
version-control tools called SCCS (Source Code Control System) or RCS
(Revision Control System). 3. n. A small quantity, but not as small as
epsilon. The jargon usage of delta and epsilon stems from the traditional
use of these letters in mathematics for very small numerical quantities,
particularly in epsilon-delta proofs in limit theory (as in the differential
calculus). The term delta is often used, once epsilon has been mentioned, to
mean a quantity that is slightly bigger than epsilon but still very small.
The cost isn't epsilon, but it's delta means that the cost isn't totally
negligible, but it is nevertheless very small.

