非 means not, un- and is a JLPT N3 kanji. It has 8 strokes and uses the not / opposite radical (非).
Stroke order · 8 strokes
On'yomi (音読み)
ヒ
Kun'yomi (訓読み)
あら(ず)
Radical
非 · not / opposite
Strokes
8
How to remember 非
Two wings facing opposite directions — they don't align, hence 'no'. 非常 means unusual; 非常口 (emergency exit) is the sign with the little green running figure.