To start using Sign Language in game, type -si console command for Mith's Virtual Console.
Sign Language is a Drow language. Sign Language was created out of necessity, because the Underdark is such a harsh and unforgiving land. Some creatures in the deep caverns have hearing that is far superior to that of other creatures (for in the dark, eyes are not as important as hearing, often); so the Drow came up with a way to communicate without sound. Since their eyesight was so well developed to living in the Underdark, it was easy for them to see and interpret signs and hand gestures. It became a valuable tool for raids, commands, formations et cetera. Sign Language should only be used on raids and in tracking and combat preparation, and then still as little as possible; as Drow tend to guard this language very carefully. They would not want others to "interpret" it and learn their secrets.
Sign Language is not really a language, but more a collection of signs and hand gestures that have a set meaning, mostly military, which are used on patrols. This means that with Sign Language you can not carry on full conversations. It is a simplified language for quick orders and reports. Sign Language is also not universal for all Drow: it differs from Drow city to Drow city, having developed certain "dialects", much like British and American sign languages differ from eachother.
- "Drow sign is more a series of orders and codes than a language; think along the lines of S.W.A.T team handsignals used as they breach a building. It likely has no signs for words such as "and", "if", "my", "yours" etc
- "wait [for] signal, attack [from] flank" is likely the kind of sentence that you could assemble, where the words in parenthesis are inferred by context, rather than actually being signed individually."
On Arelith this language is known by: