Running Multiple IE Browsers on same machine

Problem: 
Running Internet Explorer 7 Internet Explorer 8 Internet Explorer 9 on same machine.

Solution: 
If you have IE9 installed in your machine, you can test how your site works in IE7, IE8 too. When you are in the page you need to test in IE7 browser, Open "Tools"->"developer tools" or press F12. 

And then in the menu of that "Developer tools" dialog box, Click on "Browser Mode:[CURRENT MODE]" and there you can select 3 options. that is,

1. IE7
2. IE8
3. IE9
4. IE9 Compatibility Mode