  In this article, the authors give a survey on the recent developments of both
the John--Nirenberg space $JN_p$ and the space BMO as well as their vanishing
subspaces such as VMO, XMO, CMO, $VJN_p$, and $CJN_p$ on $\mathbb{R}^n$ or a
given cube $Q_0\subset\mathbb{R}^n$ with finite side length. In addition, some
related open questions are also presented.
