Node.js website memo

Use TypeScript with node.js modules

To code with TypeScript in node.js, the node.js modules must be installed with [tsd](https://github.com/DefinitelyTyped/tsd) to generate the TypeScript definition files for modules, e.g, in shell/cmd, if I want to install express and passport, I need to run:

npm install tsd -g
tsd install express
tsd install passport