How to handle frame in WebDriver?

Select iframe by id 
driver.switchTo().frame(“ID of the frame“);

Locating iframe using tagName driver.switchTo().frame(driver.findElements(By.tagName(“iframe”).get(0));

Locating iframe using index
frame(index) driver.switchTo().frame(0);

frame(Name of Frame)  
driver.switchTo().frame(“name of the frame”);
frame(WebElement element)
Select Parent 
Window driver.switchTo().defaultContent();