Selenium 2.53 and mozilla 38, when i run script it gives out

I am using Selenium 2.53 and mozilla 38, when i run below code it gives out this error


ERROR :Exception in thread "main" java.lang.UnsupportedClassVersionError: org/openqa/selenium/TakesScreenshot : Unsupported major.minor version 51.0

import org.openqa.selenium.firefox.FirefoxDriver;


public class Drivers_type {


public static void main(String[] args) {
FirefoxDriver fd =new FirefoxDriver();
fd.get("https://www.google.com/");


}

}