幸好 (xìnghǎo) is an adverb meaning 'fortunately, luckily' — it expresses relief that a situation turned out well, often averting a bad outcome. It is very close to 幸亏 (xìngkuī), but 幸好 is slightly more general and can be used for any lucky break, while 幸亏 often emphasizes that a specific circumstance prevented something worse. Unlike 多亏 (duōkuī, a verb meaning 'thanks to'), 幸好 does not introduce the person or thing to thank.