I use the website www.PrintW9.com for a lot of info concerning these forms.
It is a form often used for gaining the information from those people to whom you pay money, who are a sole proprietor, and for other purposes. Here's an example of many:
If you hire a person to come to your place of business to cut the hedges around the huge building once a month during the growing season, and you pay him/her more than $600.00 a year, then you have to send them a 1099 form right after the year end to take the deduction of the expense.
You also have to file a copy of the 1099 with the IRS for the tax filing.
The W9 form asks a lot of questions. Depending on what you are doing, it changes what you fill in on the form.
A lot of sole proprietors fill in name, address, check the sole proprietors box add their social security number, and the date and that is it for them.
Pages 2, 3 and 4 are instructions on how to use the form, but page 1 is what is filled out and submitted. In the end if you have done it once you will find it very easy to use and not even worry about any difficulty in filling it out.
If you speak and read Spanish you might like the Spanish W9 Form.
If you are a student or a borrower you can use the W9S form.
Have a beautiful and wondrous day!