The two kinds of manifestation, or appearance, 須現 the necessary appearance in the flesh of the Buddha for ordinary people, and 不須現 the non-necessity for this to those of spiritual vision.

A Dictionary of Chinese Buddhist Terms, William Edward Soothill and Lewis Hodous

（名數）佛之尊特身相好，有須現不須現二者，須現者，為中道之智眼。未開者，現起丈六之應身，廣大無邊之身相也。不須現者，中道之智眼已開者，觀丈六之佛身，為周遍法界之妙身，故佛不必更現廣大之尊特相也。如法華之龍女見佛之三十二相，讚嘆為微妙淨法身者。此中須現為別教之機，不須現為圓教之機，因之華嚴以兼別教之故，謂為須現之尊特。法華以純圓之故謂為不須現之尊特。見觀經妙宗鈔下。

丁福保《佛學大辭典》