Install TypeScript

Refer to the TypeScript's site: https://www.typescriptlang.org/index.html#download-links

Microsoft Windows [Version 6.1.7601]
Copyright (c) 2009 Microsoft Corporation.  All rights reserved.

C:\windows\system32>npm install -g typescript
npm http GET https://registry.npmjs.org/typescript
npm http 304 https://registry.npmjs.org/typescript
C:\Users\genhan.chen\AppData\Roaming\npm\tsserver -> C:\Users\genhan.chen\AppData\Roaming\npm\node_modules\typescript\bin\tsserver
C:\Users\genhan.chen\AppData\Roaming\npm\tsc -> C:\Users\genhan.chen\AppData\Roaming\npm\node_modules\typescript\bin\tsc
typescript@1.8.10 C:\Users\genhan.chen\AppData\Roaming\npm\node_modules\typescript

Then, you need to add the installation directory (C:\Users\genhan.chen\AppData\Roaming\npm), which varies from different computers, into the environmental variable list.