Selenium and Javascript
Selenium is automation tool for testing web applications. 
We will create test with Javascript, Firefox, Node.js. This test will open Firefox browser and search for string Selenium.
Installation
//Install Node.js and Npm
//Install Gecko Driver for Firefox
wget https://github.com/mozilla/geckodriver/releases/download/v0.29.0/geckodriver-v0.29.0-linux64.tar.gz
tar -xvzf geckodriver*
chmod +x geckodriver
sudo mv geckodriver /usr/local/bin/
Create new folder and inside that index.js.
npm init
npm install selenium-webdriver@3.6.0  //latest version didnt work for meindex.js
const { Builder, By, Key, util } = require('selenium-webdriver');
async function example() {
  let driver = await new Builder().forBrowser("firefox").build();
  await driver.get("http://google.com");
  await driver.findElement(By.name("q")).sendKeys("Selenium", Key.RETURN);
}
example();
Run it with:
node index.js