They communicate with each other by ear position, body language, spitting and humming. Llamas usually only spit at other llamas to establish dominance and do not spit at people. For more details go to the Behavior section of Llamapaedia. Llamas and alpacas have colorful light greaseless wool which can be used for all types of projects. It is collected by shearing or brushing.
Camelid wool is different than sheep wool in a number of ways.
To learn more about llama fiber and its uses go to the Wool section of Llamapaedia.