Basically, certain people who came to the United States as children and meet other key guidelines may request, on a case-by-case basis, consideration of deferred action. Here are some details, from the USCIS press release:
Individuals requesting consideration of deferred action for childhood arrivals must submit Form I-821D, Consideration of Deferred Action for Childhood Arrivals; Form I-765, Application for Employment Authorization (with accompanying fees); and an I-765WS, Worksheet. USCIS recently developed a series of resources to inform the public on how the process will work. The website, www.uscis.gov/childhoodarrivals, includes a flier, a How do I brochure, frequently asked questions, and a number of other resources. USCIS encourages individuals with questions to visit this website or call the USCIS National Customer Service line at 1-800-375-5283.It sounds like a lot of crap to fill out, and many hoops to jump through. But that's the Department of Homeland Security, and this is the process. For further information on requesting deferred action for childhood arrivals, follow the guidelines outlined on the USCIS website here.
USCIS is aware of immigration scams surrounding the deferred action for childhood arrivals process. Often, unauthorized practitioners of immigration law may try to take advantage of individuals by charging a fee to submit forms to USCIS, or to provide other services. The USCIS website www.uscis.gov/avoidscams includes tips on filing forms, reporting scams and finding accredited legal services.