Final answer:
President Obama changed immigration policy in the USA through an executive order in 2014, providing temporary legal status and halting deportations for certain undocumented immigrants with U.S. citizen or legal permanent resident children.
Step-by-step explanation:
President Obama changed immigration policy in the USA through an executive order issued in 2014. This order provided temporary legal status to many illegal immigrants and allowed for a halt on deportation. It particularly focused on protecting undocumented immigrants with children who are U.S. citizens or legal permanent residents. This change aimed to address the backlog of immigration cases, provide relief for undocumented individuals, and prioritize family unity.