Windows MD5 software
Lots of times when you download something from the internet you might be given an "MD5" sum as well. It's a string of 32 characters that can be letters or numbers and might looks something like this: 39b7b778a278b02be72b53e75c0225e2 The reason sites provide this is to allow you to verify that the file you downloaded came in properly and is complete and wasn't tampered with. If you have windows and you want to verify an MD5 hash sum, you can install WinMD5Sum This will add a new item when you right click on a file under the "Send To" menu. If you send a file to WinMD5Sum it'll show you the hash number. If it matches the one you got on the web site you originally downloaded from you can be sure the file downloaded exactly as expected.