Private or Alternative loans can be used to make up the difference between what your school offers you and what you have to pay. Alternative loans are not federally guaranteed and can take several weeks to process. Typically, the lower the cost of the loan, the more restrictive it is.
Also, your eligibility for alternative loans may be affected by your government loans, whether your school participates in the FFELP or the FDLP program, and other factors.
Some private loans will have set limits on how much you can borrow; however, it is much more common for private lenders to have variable loan limits that are based on an amount set by your school. Some private loans may offer options to international students who do not qualify for federal loans.
Lenders such as banks, credit unions, and savings & loan associations provide private loans. The federal government regulates private loan programs, but the loans are provided and guaranteed by private lenders and guarantors. Private loan programs will vary by lender. Private loans tend to have somewhat (and in some cases, significantly) higher interest rates than federal student loans, and may use your credit score as a basis for determining your particular interest rate. Additionally, there is no such thing as a subsidized private loan; you are responsible for all the interest.