Selenium Webdriver script | Open new browser tab and switch between tabs

In Selenium Webdriver script how to open a new browser tab and then switch between first browser tab and 2nd browser tab?

Solution: This is the script to achieve it, go through comments in the code to understand how the code works:

public static void main(String[] args) throws InterruptedException
{
    WebDriver driver = new FirefoxDriver();
    driver.manage().window().maximize();
    //URL of 1st Tab which is opened by default on  browser launch
    driver.get("http://www.google.com");
    // tab timeout - let the browser load the page  
    driver.manage().timeouts().implicitlyWait(10, TimeUnit.SECONDS);
    // Open 2nd tab now
    driver.findElement(By.cssSelector("body")).sendKeys(Keys.CONTROL + "t");
    //load a new website in 2nd Tab
    driver.get("http://www.gmail.com");
    //tab timeout - let the browser load the page    
    driver.manage().timeouts().implicitlyWait(10, TimeUnit.SECONDS);
    // perform some operation on 2nd tab if needed	
    driver.findElement(By.id("gmail-sign-in")).click();
    driver.findElement(By.id("Email")).sendKeys("WebDriver");
    driver.findElement(By.id("Passwd")).sendKeys("WebDriver");
    driver.findElement(By.id("signIn")).click();
    Thread.sleep(2000);
    // Switch back to first tab  
    driver.findElement(By.cssSelector("body")).sendKeys(Keys.CONTROL + "\t");
    driver.switchTo().defaultContent();
    Thread.sleep(2000);
    driver.close();
}
}