n is a module of Node, the author is TJ Holowaychuk (the famous Express framework author)
Installation is very simple:

$ sudo npm install -g n

After the installation is completed, input N and output the currently installed Node version and the version you are using (there is an O). You can choose the version to be used by moving the upper and lower arrow keys, and finally press the car to take effect.

$ n
    0.10.1 
    0.10.15 
o   0.10.21 
    0.11.8

If you want to install other versions (such as 0.11.12), then as follows:

$ n 0.11.12
install : 0.11.12
   mkdir : /usr/local/n/versions/0.11.12
   fetch : http://nodejs.org/dist/v0.11.12/node-v0.11.12-darwin-x64.tar.gz
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Install the latest version

$ n latest

Install stable version

$ n stable

Delete a certain version

$ n rm 0.10.1 

to execute the script with the specified version

$ n use 0.10.21 some.js

Later, I gave up n (except for being unhappy, and I did not find how to configure Taobao source), specializing in NVM