These days, most of the people wish to go to USA for many reasons. Higher qualification, business purpose or may be a permanent residence. To fulfill all these wishes, the basic thing that you must have is US visa. There are a lot of us visa application seen these days. What you must know before going through the processes of having having visa is that you must have proper documents and for that you must consult a visa consulate. Two types of visa are immigrant visa and non immigrant visa which for people who do not wish to reside their forever.