Answer:
Immediate Relative – these visas are based on a close family relationship with a U.S. citizen, such as a spouse, child or parent. The number of immigrants in these categories is not limited each fiscal year.
Family Preference – these visas are for specific, more distant, family relationships with a U.S. citizen and some specified relationships with a Lawful Permanent Resident (LPR). The number of immigrants in these categories is limited each fiscal year.
Keep in mind that U.S. citizens can file an immigrant visa petition for their:
• Spouse
• Son or daughter
• Parent
• Brother or sister
U.S. Lawful Permanent Residents can only file an immigrant visa petition for their:
• Spouse
• Unmarried son or daughter
Explanation:
this is from google but it simplifies it as much as possible
