[sentinalien]

How do all these people immigrate to the US? Is it all family-based? I work in technological field with many more opportunities in the US and have researched how to move there but it seems almost impossible. I know an American who applied for jobs in my country, got an offer and was over within a few months but that doesn't work the other way round.

[relaxing]

You fly over and overstay your visa (indefinitely.) Neglecting any discussion of the legal ramifications, that is largely how it happens.

[thyrsus]

And then you have no legal standing, so you get paid far below market depressing everyone's wages, and in any dispute you get deported. The best thing for workers would be for there to be no such thing as an "illegal alien" - but xenophobia/racism wins instead.

[karp773]

Yes, it's mostly family-based. If you look at the distribution of the categories of the issued green cards, ~2/3 are through family. Employment based green cards are less than 15%.