What is the purpose of ngSwitch directive?

NgSwitch directive is similar to JavaScript switch statement which displays one element from among several possible elements, based on a switch condition. In this case only the selected element placed into the DOM. It has been used along with NgSwitch , NgSwitchCase and NgSwitchDefault directives.
For example, let’s display the browser details based on selected browser using ngSwitch directive.

<div [ngSwitch]="currentBrowser.name">
  <chrome-browser    *ngSwitchCase="'chrome'"    [item]="currentBrowser"></chrome-browser>
  <firefox-browser   *ngSwitchCase="'firefox'"     [item]="currentBrowser"></firefox-browser>
  <opera-browser     *ngSwitchCase="'opera'"  [item]="currentBrowser"></opera-browser>
  <safari-browser     *ngSwitchCase="'safari'"   [item]="currentBrowser"></safari-browser>
  <ie-browser  *ngSwitchDefault           [item]="currentItem"></ie-browser>