Hello Kartik, following piece of code can help you in understanding Implicit wait and how it can be used in Selenium:
import java.util.concurrent.TimeUnit;
import org.openqa.selenium.By;
import org.openqa.selenium.WebDriver;
import org.openqa.selenium.firefox.FirefoxDriver;
import org.testng.annotations.Test;
public class VerifyTitle
{
                @Test
                public void verifyPageTitle()
                {
                                WebDriver driver=new FirefoxDriver();
                                driver.manage().window().maximize();
                                driver.get("http://www.facebook.com");
                                // Specify implicit wait of 30 seconds                                   
                                 driver.manage().timeouts().implicitlyWait(30, TimeUnit.SECONDS);
                              // No login id is present on Webpage so this will fail our script.
                                driver.findElement(By.id("login")).sendKeys(" Abha Rathour");
                }
}