H1B visas are just work visas for “highly skilled labour” to immigrate to the United States. There’s a cap of ~65k issued per year, and it’s usually used by large tech conglomerates and other large companies to hire foreign labour and bring them to the United States. A lot of these H1B visa immigrants are South Asian because India has the most IT specialists in the world and many of them speak good English. There’s like a right wing civil war going on right now where Elon and co say they need H1Bs because native born Americans don’t work as hard as immigrants (which in my experience is true, immigrants always work harder, highly paid or not, since immigration is already self selecting and they went through a lot of work to immigrate and are primarily motivated by money hence the economic migration) and the white supremacist MAGA guys saying H1Bs are contributing to the Great Replacement or whatever.