You've got nothing to fear, even if you're here without papers. Every ten years, the U.S. government gathers information about the country's population. City, state and federal governments use this information for deciding how to distribute funds for education and health care, and other purposes important to your community.
Some undocumented immigrants are afraid to send in the forms.
However, I'm convinced that information about individuals won't be given to the INS or other enforcement agencies. I'm telling all my undocumented friends and clients to send in the forms. If you don't send in the form, a census worker will come to your home to gather information. Avoid that inconvenience by sending in your form.