kim-codes

const vscode = require('vscode');

function activate(context) {

    let disposable = vscode.commands.registerCommand('extension.dictionarylookup', function () {

        vscode.window.showInformationMessage('THIS IS DISPLAYING A MSG TO THE USER :)');
    });

    context.subscriptions.push(disposable);

kim-codes

const vscode = require('vscode');

function activate(context) {

    let disposable = vscode.commands.registerCommand('extension.dictionarylookup', function () {
        var editor = vscode.window.activeTextEditor;
        var selectedText = editor.document.getText(editor.selection);
        vscode.window.showInformationMessage('The word you selected is ' + selectedText);
    });
    context.subscriptions.push(disposable);