TACAN

Stands for TACtical Air Navigation http://en.wikipedia.org/wiki/TACAN

Provides the user with a distance and bearing from a ground station.

Unified Modeling Language (UML)

An object-oriented analysis and design language.

http://www.pcmag.com/encyclopedia_term/0,2542,t=UML&i=53392,00.asp

Specification and Description Language (SDL)

A modeling language used to describe real-time systems.

Digital Aeronauticl Flight Information File (DAFIF)

DAFIF stands for Digital Aeronautical Flight Information File. This is used in

http://en.wikipedia.org/wiki/DAFIF

a complete and comprehensive database of up-to-date aeronautical data, including information on airports, airways, airspaces, navigation data and other facts relevant to flying in the entire world, managed by the National Geospatial-Intelligence Agency (NGA).

Source lines of code (SLOC)

Source lines of code (SLOC) - refers to measurement of the size of a software program.

See: http://en.wikipedia.org/wiki/Lines_of_code