How to execute scripts in parallel in selenium

How to execute scripts in parallel in selenium:
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By using testing.xml we can execute the test cases parallel

TestOne.java:

=============

package com.rs.blog;

import org.testng.annotations.Test;

public class TestOne {

       @Test

       public void scriptOne() {

              System.out.println("script one");

       }

}

TestTwo.java:

===============

package com.rs.blog;

import org.testng.annotations.Test;

public class TestTwo {

       @Test

       public void scriptOne() {

              System.out.println("script one");

       }

}

Testing.xml:

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<?xml version="1.0" encoding="UTF-8"?>

<!DOCTYPE suite SYSTEM "http://testng.org/testng-1.0.dtd">

<suite name="Suite" thread-count="3" parallel="methods" >

  <test name="Test">

    <classes>

      <class name="com.rs.blog.TestTwo"/>

      <class name="com.rs.blog.TestOne"/>

    </classes>

  </test> <!-- Test -->

</suite> <!-- Suite -->

Thread-count:  If the thread count is 3 so 3 web driver instances can run parallel in 3 different browsers

Parallel:

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The parallel attribute of suite tag can take three values:

1                              Tests: All the test cases inside <test> tag of testing xml file will run parallel

2                             Classes: All the test cases inside a java class will run parallel

3                              Methods: All the methods with @Test annotation will execute parallel