Generally, if the relative or friend wants to visit (and not live in) the United States, and they are from a visa-waiver / ESTA country (http://www.esta.us/visa_waiver_countries.html), no visa will be required. The individual can generally enter the US for up to 90 days as long as there are no criminal or previous US immigration issues in that individual’s past. The 90 day limit is final in most circumstances.
If the relative or friend is from any other country, they must first obtain a B2 visitor visa at their local US Embassy (https://www.usembassy.gov). Each US Embassy has their own local filing procedures and documentation needs listed on their website in English and the native language. The most difficult aspect of the application is proving “non-immigrant intent”. Essentially, the individual must prove to the officer that they will return home after their temporary trip to the US. This can be extremely difficult from countries that may be experiencing turmoil.
Relatives or friends that want to visit the US for the major end-of-year holidays may want to start their application process soon since it can take weeks for the final decision to be issued.
Contact the Schunk Law Firm PC for assistance.