A citizen/resident of a foreign country should first a obtain a visa to gain entry into the United States. Primarily there are 2 types of US visa: either a nonimmigrant visa for temporary stay or an immigrant visa for permanent residence

Foreign nationals who want to to enter the U.S. should usually get a visa. Visas are divided into 2 general categories:

✦ Immigrant
✦ Nonimmigrant

Immigrant visas are issued to those people who are seeking permanent residence within the U.S., whereas nonimmigrant visas are issued to those people who stay for a limited period of time with a specific purpose.
F-1 visa F-1 visa is usually granted to students for his/her academic degree, for full time courses, valid till the duration of their study period and is not valid for employment. For students planning to extend their stay or to work in US, after the completion of their studies, they need to apply for H-1B visa.
H-1B visa is given out on a lottery system because the demand for H1B visa is more than the supply and it is important to get H-1B visa in order to work in US for students
H-1B visa The H-1B visa is very popular. In order to obtain an H-1B, one must have an offer of employment from a U.S. employer. His/her proposed job position must be in a specialty occupation, which usually means that a bachelor’s degree or higher is required to do the job. The U.S. employer must sponsor the H-1B visa by filing an I-129 Petition with U.S. Citizenship and Immigration Services (USCIS).
H-2A Visa A H2A visa is mainly a visa provision that allows US citizens to bring nationals from other countries for work in the agricultural fields.
H-2B Visa H-2B visa is granted to people who are planning to come to US for a job which is temporary or seasonal in nature. Employer has to produce a certificate approving that for their position there are no employees in US.

✦ F1 visa is for students planning to go for higher studies abroad.
✦ One must have a bachelor’s degree or higher degree in the specific sector that they seek employment in order to get H-1B visa.
✦ H-1B visa is allotted by lottery system.

✦According to Department of Homeland Security (DHS), the rate of suspected overstays for business travelers and international tourists was .9% in 2015. That calculates to 416,500 travelers out of about 45 million tourists and business travelers.
✦ In fiscal year 2016, the United States issued 10,381,491 nonimmigrant visas and 617,752 immigrant visas.
✦ In 2016, the United States issued 482,033 F-1 visas.

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