What is the difference between a woven and nonwoven (TERRAM) geotextile?

A woven geotextile is manufactured from continuous filaments or strips of synthetic material which are woven together to form a uniform sheet. A woven geotextile has a very uniform pore size which varies under load making them less suitable for filtering anything other than clean single sized soils/fills. Nonwoven geotextiles are a tangled web of fibres mechanically and/or thermally bonded together to form a non-uniform random web. Nonwoven TERRAM geotextiles have a wide range of pore sizes which make them ideally suited for filtering many different types of fill materials including well graded materials even under varying load conditions.