If you're reading this then you are no doubt looking for the owner or source of a specific number. There could be a number of reasons why you need to do this, but what's more important is that you get results. Here's how you can do this simply using Google.
The first step is to take the number that you have and enter it into the Google search field. This is the same search field that you would use to look up any term in order to find results for web pages.
After you click search you may find what you were looking for, but if not, try entering the number in "quotations" because this can improve results. If you still do not find the number that you are looking for, you can try using (parenthesis) because this can sometimes also improve results.
If even at this point you are not seeing the results that you were expecting, you have two more options. You can either crowd the numbers together (5555555555), or insert hyphens in between (555 – 555 – 5555).
If after all of this you can not locate the number that you want, there are two reasons for this. If the number is unlisted or is a cell phone number then it will not show up in a simple search engine results page.
If this is the case then you will need to use an actual reverse phone number search service. These are generally very cheap, fast, and easy to use, and will often times give you more information than you originally expected.
There are lots of services like this that people use every day, but you must understand that they are not all the same. Make sure that if you decide to go this route, that you do your research to find the best reverse number lookup.