a) Single Page Applications
b) Streaming Data
c) A Real-time Applications like online games, collaboration tools and chat rooms etc.
d) I/O bound Applications
e) APIs based Applications
f) JSON based Applications
g) PROXY Applications
a) Nested callback hell.
b) In Node.js, any CPU intensive computation will block the responsiveness.
c) Dealing with files can be a bit of a pain.
d) In Node.js, the relational database is a bit of a pain.
e) It's asynchronous programming model not for synchronous model.