Welcome to your first VS Code Extension

What's in the folder

This folder contains all of the files necessary for your extension
package.json - this is the manifest file in which you declare your extension and command. The sample plugin registers a command and defines its title and command name. With this information VS Code can show the command in the command palette. It doesn’t yet need to load the plugin.
extension.ts - this is the main file where you will provide the implementation of your command. The file exports one function, activate, which is called the very first time your extension is activated (in this case by executing the command). Inside the activate function we call registerCommand. We pass the function containing the implementation of the command as the second parameter to registerCommand

execute npm install in a command line to restore the add-on dependencies
press F5 to open a new window with your extension loaded
run your command from the command palette by pressing F1 and typing 'Hello World'
set breakpoints in your code inside extension.ts to debug your extension
find output from your extension in the debug console

you can relaunch the extension from the debug toolbar after changing code in extension.ts
you can also reload (Ctrl+R or Cmd+R on Mac) the VS Code window with your extension to load your changes

you can open the full set of our API when you open the file node_modules/vscode/vscode.d.ts