What's the difference between immigrant and non-immigrant "intent"? The type of visa is determined by the purpose of the travel to the United States.
Immigrant Visa
An immigrant visa is for someone that intends to immigrate to the US or permanently live in the United States. Most immigrant visas have a path to citizenship after a number of years of lawful permanent residency.
Examples of immigrant visas include (but are not limited to): CR1 or IR1 Spousal Visas; IR5 Parent Visas; IR2 Child Visas.
Non-Immigrant Visa
A non-immigrant visa is for someone who intends to come to the United States on a temporary basis, and has no goal for a path to citizenship.
Examples of non-immigrant visas include (but are not limited to): B1/B2 Tourist Visa; Student Visas; Exchange Visas; Temporary Worker Visas.
K1 Fiance Visa - A Unique Hybrid
Uniquely, the K1 fiance visa, while technically a non-immigrant visa, is processed as if it were an immigrant visa. On a fiance visa, the intent is to come into the U.S., marry a U.S. citizen and stay permanently. But the visa status is only temporary. Once you enter the U.S. on a fiance visa, after the marriage, you would apply to adjust status to officially change from a non-immigrant to an immigrant.