There are various Immigration laws that have to be followed in order to cross from one country to another. When someone applies for a passport to travel from his country of residence to another country, or wishes to enter another country for employment or educational purposes, these actions are part and parcel of International Immigration law. Every country has its own immigration law. The United States of America calls every person who is not a natural born citizen as an "alien" and specifies various processes under which he can enter the US, gain residence and obtain full US citizenship rights by becoming a naturalized citizen.

The United States of America is a land of opportunities. It is a place where many aspire to go and settle. However this is not as easy as it may seem. Obtaining a US visa remains a dream for most of the aspirants who wish to migrate to the country. Although air travel costs have reduced over the years, migration remains difficult, expensive and potentially dangerous if illegal crossing is involved.

But fortunately, there is some respite for these people. There are some specialized law firms whose expertise is in getting immigrants a valid US visa. These firms have skilled lawyers whose expertise lies in not only getting immigrants a Visa but also enabling them to become a permanent citizen of the country. They take care of all the technical paperwork in compliance with the immigration laws. These firms purpose is to help business professionals and family members of citizens obtain a variety of different types of visas and will process petitions on your behalf and represent you to the necessary government agencies. 

There are many types of Visas that you can get in order to migrate to US.

Business Visas

Professionals who wish to travel to US for their job responsibilities travel on a business visa. Executives, investors, yacht crewman, journalists, extraordinary artists, athletes and other laborers fall under this category.

Family Visas

Family visas have to be obtained for spouses, children, parents, siblings and fiancées of United States citizens. An improper petition might deprive a family member of this Visa, hence the services of an attorney is highly critical here.

Temporary Worker Visa

A worker who seeks to enter the United States temporarily for a specific purpose and is bound to leave the country afterwards, must obtain this type of visa.

E-1 treaty traders and family of E-1 treaty employees

Any country that has a treaty with the United States on Commerce and Navigation can send its national to engage in international trade on the countries behalf. Such a person gets an E-1 treaty Visa. Certain employees and related family members of such a person also fall under this type of Visa.

H-1B

This visa category applies to people who wish to perform services in a specialty occupation, services of exceptional merit and ability relating to a Department of Defense (DOD) cooperative research and development project, or services as a fashion model of distinguished merit or ability.

H-2A Temporary Agricultural Workers

The H-2A program allows U.S. employers to employ foreign nationals for temporary agricultural jobs for which U.S. workers are not available. H-2B visa applies to the same but for non-agricultural workers.

L-1A Intra company Transferee Executive and L-1B transferee with specialized knowledge:

The L-1A non immigrant classification enables a US employer to transfer an executive or manager from one of its affiliated foreign offices to one of its offices in the United States. The L-1B non immigrant classification enables a US employer to transfer a professional employee with specialized knowledge relating to the organization’s interests from one of its affiliated foreign offices to one of its offices in the United States.

Resource: http://www.miami-droit.com