A Triple-Slash Directive is a single-line comment that contains a single XML tag. You can use the content of the comment as a compiler directive.
They are only valid at the top of their containing file. A triple-slash directive can be preceded only by single or multi-line comments, including other triple-slash directives. Below listed are some of the triple-slash directives in TypeScript :
/// <reference path="..." />
This directive allows a file to include an existing built-in lib file explicitly.
/// <reference no-default-lib="true"/>
This directive marks a file as a default library.
