B-1/B-2
(1) B-1
You may be eligible for a B-1 visa if you will be participating in business activities or a commercial or professional nature in the United States, including: consulting with business associates, traveling for a scientific, educational, professional or business convention, or a conference on specific dates, settling an estate, negotiating a contract, or participating in short-term training. The initial period of stay is 1 to 6 months, 6 months being the maximum allowed stay. The stay can be extended up to 6 months, with the maximum total amount of time permitted in B-1 status on any one trip being 1 year. You will enter with this business visa if you have a business in Korea and need to enter the United States on a business trip to enter the U.S. market or as a preliminary investigation to establish a branch office in the United States.
(2) B-2
The B-2 visa is a nonimmigrant visa for visitors who wish to enter the United States temporarily to visit friends or family, or travel to the United States. In most cases, a period of a stay of 6 months is permitted, with the possibility of an extension under certain conditions. You can enter and study in the United States on a tourist visa to receive short-term language training of less than 18 hours per week, even if you do not have a student visa. However, in the case of Korea, it has become difficult to apply for or extend a tourist visa after visa-free entry is allowed.
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