Visa Regulations in the USA
While visiting Miami, there are some visa regulations that everyone should follow. Travelers wishing to visit Miami should learn some information, whether they will need an ESTA or a full visa and that having only a valid passport is not enough. In most cases, travelers need ESTA (Electronic System for Travel Authorization) which means that they can hold it instead of a visa while traveling across the US. The difference between ESTA and Visa is that with ESTA you are eligible to travel to the US legally for a period of 2 years. A maximum of days you can stay in the US consecutively is 90 days, but you won't have to re-apply for a new one while booking a new flight to the US during those 2 years. One thing to take into account is that citizens of only 38 states can apply for ESTA. Also, it is not allowed to work while staying in the US. It is important not to stay there for longer than 90 day period as this may result in future tries of accessing the US.
ESTA is also called “Visa Waiver Program”. If you live in a country which is not under this program, then you will have to apply for the full visa. Getting a full visa usually gives the ability of only a single visit and for a specific amount of days. This kind of visa requires a personal interview. There are many other kinds of visas, specially created for travelers with specialty occupations. There is also a variety of visas for executives and managers (L-1A), for people with extraordinary ability or achievement (O-1), for Treaty Traders and employees (E-1), and so on.
A different case is when the traveler wants to get an immigrant visa in order to move to this city permanently. The most notable immigrant visa is Green Card, which can also be won through the annual lottery around the whole world.