Could you please explain what the H1B US visa is?

The H1B visa is a non-immigrant visa that allows US companies to employ foreign workers in specialty occupations that require theoretical or technical expertise in a specialized field. This visa is popular among technology companies and other industries that rely on highly skilled workers from other countries. To be eligible for an H1B visa, the applicant must have a job offer from a US employer and must have the appropriate qualifications for the job. The visa is typically granted for three years, and can be renewed for an additional three years.