Type Annotations​

• What: Like type declaration in Java.
• How: Syntax as following:

variable: type;

ES/TS Primitive Types​

boolean​

let bool: boolean = true;

npm (Node Packaged Modules) is node's official package manager. You can also see all the versions of node and corresponding npm here.

Overview​

npm CLI documentation

Acronym​

-g​

--global 缩写为 -g，表示安装之后的包将位于系统预设的全局目录之下。

-S​

--save 缩写为 -S，表示安装的包将写入 package.json 里面的 dependencies。